Newbie Seed Starter - Last year failed!

Springfield, IL(Zone 6a)

I'll say thank you first- I have quite a few questions for you all!

I tried to start seeds last year and got some growing but ended up failing miserably in the end. I have two of those metal "greenhouse" things with a plastic double zip cover with four shelves and one with two shelves. I also have clip-on lights with grow bulbs I used to start the seeds. I used open trays (no individual openings) with seed starting soil and planted the seeds, labeled the sections and used plastic fork/spoon handles with string between as labels and to block off the areas for each seed type. I ended up with most of them coming up but being very fragile and thin. I also ended up with gnats (ick!) and I think too much moisture in the trays. My (dearest) husband took some of my trays outside to try to get them healthier and ended up leaving them out in heavy rain and they drowned. I was not happy. Nothing I planted survived and I was so disconcerted that I gave up. I want to try again this year with tropicals, perennials, and veggies- same as last year. Here are my questions:

1) Should I get coir discs and plant 1 or 2 seeds in each disc?
2) How do I keep gnats away?
3) Should I put different types of seeds in each different "greenhouse" and if so, how do I know what to put with what?
4) How do I grow them with out them ending up so delicate?
5) How much water is too much? The greenhouses get condensation on the insides of them- how do I know how to water the seeds/seedlings?
6) What kind of lighting schedule should they be on?
7) I'm zone 5b- when do I need to start the seedlings?

If there's anything else I didn't ask, please let me know. If there's a book I should read or some step-by-step guide that would be better for me, please let me know. I don't have as much money this year and won't be able to blow it on full grown plants, thus I want to grow my own from seeds. Thanks again for your help- I REALLY appreciate it!!! :)


Clover, SC

I hope you'll try again this year! Starting your own seeds is fun and rewarding.

When it comes to tomato seeds, use containers with individual units rather than a flat. This way, when plants have 2 sets of leaves and it's time to transplant them to larger containers, you won't have to separate their root systems. Keep soil evenly moist. Don't let it dry out but don't let it get soggy, either. In order to germinate, seeds need light and warmth, along with moist (but not too wet) soil. Here is a page that may help:

The trays likely attracted gnats from over-watering.

As to when to start your seeds, check this page about when to start tomato seeds in your area:

Re: lighting. Tomato seeds need 12-18 hours a day to germinate. But they also need the darkness, so don't leave them under lights 24 /7.

Once seedlings have 2 sets of full leaves, transplant them to larger pots. Here's a page that will help:

Here's some basic seed starting advice:

Good luck!

Galesburg, IL

To answer some of your questions in order.

1. I don't use coir discs or peat pellets, or anything else that is pre-sized and compressed. I use good quality seed starting mix that I pre-moisten and let sit for a couple of hours after adding water to let the mix equalize. If you can squeeze any water out of the mix, it is too wet and you need to add a little more mix. If its too dry, you won't be able to form it into a loose "ball" with your fist.

2. As Kathy said, the gnats are likely a function of over watering. They are fungus gnats and the fly that you see does no damage to the plants, but is very annoying. The larvae lives in the soil and in some rare cases, can be a pest by feeding on seeds before they germinate. Keep watering to a minimum and they shouldn't be a problem.

3. You don't need to dedicate your greenhouses to a certain type of seed as long as the seedlings are separated by cell packs or by trays so you can move seedlings as needed once they have germinated. Don't plant different things in the same cell packs or you might have some things emerged while others haven't yet germinated. I will mix 6-packs of many different plants in the same tray to start germination, buy I can then move individual 6-packs as they germinate and grow. The only reason to segregate is if you need different germination temperatures for different plants. I germinate most perennials much cooler than my veg and the perennials all start in my basement under lights (62 degrees) while plants that need warmer temps are started upstairs under lights ranging from 70-75 degrees.

4. Kathy hit it right on the head talking about light duration. I leave lights on all my seedlings for 16 hours each day. The other thing that will help produce heartier seedlings is air flow. open up the plastic once seedlings have emerged so let air move them around. Some people will also add a small fan that blows gently over seedlings. This will help produce stockier plants and will also help drying out the soil if you tend to overwater.

5. Never let water sit in the bottom of trays while you are trying to germinate or while they are growing. If while germinating seeds you see large drops condensing inside your plastic, or drops running down the side of the plastic you have it too wet and the plastic needs to come off or at least opened up to allow it to dry some. I try to water as much as I can from the bottom. I will add water to the trays the plants are sitting in and watch the surface of the soil. As soon as you can see some moisture wicking to the soil surface, drain all the water out of the trays. As to when to water, watch the plants themselves. When you start to see them droop just a little bit, it is time to water. Another way I determine when to water is by picking up the trays/cell packs themselves. It takes a little practice, but you can tell when plants need water by how light the trays feel. I am constantly moving and rearranging cells/trays so you can get a feel for it very quickly.

6. All my plants get 16 hours under the lights. The only ones that don't are the plants that need darkness to germinate and those I will cover with something to keep light out until they have emerged. Also remember to keep the lights close to the top of the seedlings (within 4 inches) and rotate your trays/cell packs if needed to get even light. When I max out my space relative to my lights, I rotate all trays once a day so everything gets even light. Moving the plants around also helps produce sturdier plants the same as having a fan or other airflow.

6a. I just reread your post before I sent this to see if I addressed all your questions and realized that you are using incandescent grow lights. Everything I was referring to with regard to lights and proximity to the plants is specific to florescent lights. If you keep incandescent lights close to newly emerged seedlings, you will kill them within a very short period of time as they produce way too much heat relative to the light produced. It is also difficult to get uniform light on trays of plants using incandescent lights. I only use florescent lights growing my seedlings as do most people here. If you haven't, look into getting some florescent lights that you can hang above each of your shelves, you will be much happier in your results. If you do buy some florescent fixtures, don't worry about trying to buy the expensive "grow lights", the cool white lights will give you everything your plant needs. If you are using incandescent lights inside your "greenhouse", be very careful of the temperature. These lights could very easily raise the temperature too high and prevent germination/kill germinating seed of many types of plants.

7. When to start depends on what the plant is. Here in Zone 5, our last frost date averages about April 20, so I will calculate back from there depending on the plant and the recommendation on the seed packet. I usually start peppers about the second week of March and tomatoes a week later. Many of the perennials I grow are natives which need stratification before they germinate, and they have been planted and out in the cold since the first of the year. I will bring them in about the middle of February to start germ. Right now the only thing I have planted are some Baptisia, Cassia, rosemary and some Asclepias. I have daylily seeds in the fridge now and will plant them out in a couple of weeks. I will start a lot of my annual flowers about the first week or two of February (petunia, begonia, geranium and similar slow starting plants) depending on their rate of growth but won't start things such as marigolds, zinnia, etc until about April 1.

8. Other things - Label everything well. I put plant specie, variety, date and number of seeds sown on labels that go into every container I sow. Also it is important to keep very good records on when and how you started things, it will be valuable in determining how to change things in the future and will help figure out problems if you have any. I keep my records in a spreadsheet and constantly refer back to it year after year. I also made up a little spreadsheet using the last frost date to help me keep track and calculate when to start seeds. Just enter the last frost date and have the sheet subtract the number of weeks or days before the frost date to start the seeds. When I have figured out everything I am going to start for a year I enter everything into the spreadsheet to try and keep track of what to start when. Of course this implies that I have everything planned out by now, which I definitely don't. As days go by and more catalogs are received I am constantly adding things I want to grow.

One other thing, the plants are probably at their most vulnerable when they are moved outside for the first time. Keep them out of the sun and out of the wind and slowly let them acclimate. It is really disheartening (as you know) to loose the plants after you have put so much hard work into growing them.

Finally, don't be shy about asking questions here. There is a vast amount of knowledge that people are more than willing to share.

Springfield, IL(Zone 6a)

WOW! What great responses!! Thank you so very much!!!! I am going to print out your posts and keep them by my little "greenhouses."

I definitely over watered last year- I had a lot of water running down inside the "greenhouses." So much, in fact, that they kind of looked like terrariums!

I can't afford to purchase the incandescent fixtures this year but will be very careful about the heat generated by the incandescent grow lights. I did rotate the trays frequently last year and will do so again.

trc65, thanks for the zone info. I'm 5b (I think you're 5a in Galesburg) and that info really helps. It sounds as though you don't use the pre-made stuff but you do use the 6-pack cells that are available. Do you use plastic or the recycled brown ones you can plant right in the ground? I was at Big Lots and they had 12-packs of the brown ones for something like $2. Is that a good price?

I'll probably bug you all with more questions later but I have one more right now:
I planted my seeds in trays last year not by type but by time until germination. Is this the right way to do this if you're only growing one packet of a type? Thanks!

Galesburg, IL

I do not like to use any of the preformed peat pellets or any similar type compressed media. I prefer to use a pre-mixed seed starting mix that comes loose or I mix my own from bales of peat, perlite/vermiculite and a little pelleted lime. A lot of people have reported having problems with peat pellets as they tend to stay wetter longer than some of the pre-mixes.

I much prefer using plastic cell packs over the "brown" ones (usually compressed peat). I grow upwards of 2500 plants each year, so I keep my plastic packs and reuse them until they fall apart. I usually use 806 cell packs (48 cells/tray) for vegetable transplants and 1206 packs (72 cells) for annual flowers. I will usually start my perennials in 128 plug flats and then transplant into 2.5" square individual pots. A good source that I use for cell packs and trays is the Greenhouse Megastore that is based in Danville. They have about the best prices and fast shipping (I usually have the product in hand within 3 days after ordering). I think you will be pleasantly surprised how inexpensive the plastic ones are compared to the "organic pots". It is not like other web suppliers where you have to buy cases of the product, they offer hobby packs of inserts that are only $8 for a pack of 10 sheets of cells (each sheet fits a standard 1020 flat).

You might want to check out some of the BigBox hardware stores for prices on florescent lights. You don't need the fanciest or newest type of fixture, usually you can find a four foot double bulb fixture for around $10. They also usually come with cool white light bulbs which are ideal for seed starting. If you buy some florescent lights, don't waste your money buying the specialized grow lights cool white bulbs do just fine.

Elmira, NY(Zone 6a)

I will concur with the others that light was the major problem with the seedlings last year. I use cheap shoplights with ordinary fluorescent bulbs in them but make sure they hang no more than an inch or two from the top of the seedling. This means moving them up as the seedling grows. These shoplights usually come with little chains for hanging. Then get a pack of S-hooks, they are called, to deal with changing the distance you hang the lights. The big box stores have these. Incandescent lights are worthless for starting seeds. Putting them in a window is better, and simply reverse them every day. That's what I used to do before I bought shoplights and a wire shelving unit to hang them from.

Everett, WA(Zone 8a)

First, THANK YOU for sharing that you lost so many seeds your first year. Me, too! My suggestion is to rpactice with "easy" seeds like Marigold and some vegetables, and work your way up to harder seeds like petunias.

My theory is that too much water is the hardest sin to avoid. Peaty seed mixes like jiffy grow hold enough water to drown a giraffe, and I can't seem to stop myself from watering with a mister. This year, i hope to convince myself that bottom watering really works, and just stand there sucking excess water of the trays with a turkey baster.

So I added sand and coir to Jiffy Mix last year, which helped a little. This year, I'll try coarse Perlite and chick grit or medium grit instead of sand, and pine bark instead of coir: both coarse and medium pine bark, like "orchid bark" and maybe "Orchid Mix".

If you can manage to refrain from over-watering, you're a miracle of self-control!

I believe that most fibrous sprouting mixes tend to let water "perch" in the bottom half of the cell or pot, keeping air and roots out. Maybe very-fast-draining soil will cure that.

Sometimes the Habitat for Humanity outlets have 2nd hand flourescent fictures.

I bet your incandescent lights made the soil warm, which often aids germination. If your house is kept cool, like 60-65, they might have liked that warmth, up until they emerged fom the soil. One of these years, I plan to buy a heating mat with thermostat. And a sheet of drywall (gypsum) to put under and around the trays, to keep the heat in.

My survivors really seemed to appreciate the little fan I gave them.

If you use trays of cells, like "plug trays", and some rows sprout before others, you can always cut out the green rows and move them. I usually start cuts with a sharp knife and finsih with scissors. The "inserts"? are usually pre-cut and you can easily tear them apart.

As long as I cut blocks of 3-4 rows, they still stand up and they are much more convenient sizes.

I think my other worst sin was leaving sprouts in small cells too long. And sowing too many seeds per cell, and being a wimp about thinng. And waiting too long to harden off, outdoors, becuase i knew the slugs were just waiting for their salad course.

Tom Clothier has some great advice, and, unlike me, he knows what he's talking about! (index to many pages of good advice) (soilless mixes) (germination and soil temperature) (damping off)


Calgary, Canada

I am sorry that your first attempts were not more successful.
Remember that gardening and seed germination is something that you learn by doing.
The previous posts give you good advice.
I am sure that you will be successful with some seeds this year.
Do keep us posted as to your progress.

Springfield, IL(Zone 6a)

You guys are SO great! Thank you from the bottom of my mini-greenhouse :) for all of your help without censure. I tried all different seeds last year (you should've seen the fiasco of me trying to score some of them - blood is a good growing medium, right? :) ) I soaked the ones I was supposed to soak and did what the packages said to do but I think I did too many things wrong. My main mistake was too much water. Should I purchase a mister? I don't own one. I am going to do things a lot differently this year thanks to all of you. I will keep asking for help, so thanks for bearing with me, and I will post pictures as I get things going with the little greenhouses, heat mats, and lights.

I went to a Master Gardener conference this weekend and was a bit disappointed. They had a guy talk about seed saving. He is part of a family owned company in Arthur, IL. They do cucurbits and are the only source in the world for some of these species. They talked about the seeds in terms of saving them but not in terms of starting them although they had a big booth selling seeds. I think you have to know how to get them started before you can even think of saving them! Oh well, I got to see some stunning things I'd never seen before and bought two types of rare seeds I'm going to try (cross your fingers!) to grow.

Happy day to everyone- we are getting a blizzard here!

Everett, WA(Zone 8a)

>> but I think I did too many things wrong

Me, too, exactly! I think it was Yogi Berra who explained a bad season by saying "We made too many wrong mistakes." Unfortunately, there are only a few significantly different ways to germinate successfully, but there are MILLIONS of ways to go wrong.

>> My main mistake was too much water.

Everyone tells me to "bottom water" but it seems awkward and messy. Maybe that works OK with pots that sit flat on a tray: add enoguh water that the pots are 1/4-1/2" deep, give it 10-40 minutes, then laboriously suck excess water out of the tray.

>> Should I purchase a mister?

Maybe just a spray bottle?

My theory was that my seed-strating mix (Jiffy Mix) held too much water too long, so this year I lightened it with shredded pine bark and Perlite (and wish I had chicken grit or CLEAN coarse sand).

Strong lights sound good. I may go to a Habitat for Humanity outlet to see what they have seocnd-hand.

My second main sin was leaving seedlings in cells or tiny pots too long, and inside too long. I've heard a few people say to "pot up" as soon as seedlings have 4 true leaves.

Keep trying!


Watertown, WI(Zone 5a)

You've already gotten some great answers to your questions, but I thought I'd chime in here. I'm fairly new to starting seeds indoors myself, but I've been very successful the last couple years.

In my experience, those greenhouses (I think I have the kind you're talking about) are great for moving seedlings outside in late winter/early spring but not as handy for starting seeds. I created my own setup, which is similar to many I've seen other avid seed-starters use. I have a wire shelving unit with slatted grates (as opposed to a solid bottom on each shelf) with 4 tiers, which cost me about $40 at Walmart. I added four $20 shop lights, also from Walmart. The top tier light is suspended from my ceiling on a chain that hangs from two toggle hooks. The lights on other tiers hang from the grate on the shelving unit with chains (included with most shop lights) and S-hooks (also included, although I had to buy a few extras.) The unit will hold 8 large flats and cost me about $140 total (as opposed to the ones you see in catalogs, which go for around $600.) The attached picture shows my setup's top two tiers and the seeds I've got growing already. (The larger ones on top are culinary herbs I plan to keep indoors.)

As for seed starting flats, I've discovered that flats with deeper cells give seedlings a great start by allowing their roots to grow long and deep. (We were just discussing this in the Upper Midwest forum here at Dave's.) Although they can be a bit expensive ($15-20), I'm a huge fan of Burpee's Ultimate Growing System. ( You'd think that I work for the company or something the way I rave about it. lol

The cells in this system are deep, and there's a unit that sits underneath the flat and holds water and a mat that wicks the water up to the cells and keeps the soil moist but not wet. I've never had a problem with damping off. Despite some reviews that say the seedlings are hard to remove from the cells, I've never had a problem. I use a dinner fork and they pop right out. If I'm transplanting them, the fork makes things handy because I can move the seedlings to their new homes without disturbing their roots, stems or leaves. The system is also easy to reuse. Although it initially comes with soil tablets that you moisten to make them "fluff up," this year I just added pre-moistened sterile seed starting mix (I put it in a container and sprayed it with a mister while stirring to get it evenly moist) to each cell, set up the Growing System as usual, and planted. Worked like a charm, and I didn't have to buy the pellets that Burpee sells with these systems, which are kind of expensive.

Also, I would avoid coir and peat pots and anything of that nature. I used both coir and peat pots last year and found that they kept things either too dry or too wet for my liking. This year, I switched to cheap plastic 4" pots from my local garden center (20 cents each, and cheaper in bulk) and I'm much more satisfied with them. They're easier to keep consistently moist and not overly wet. Plus, they're reusable.

There are many different ways to start seeds, as I've learned while researching. I figured I'd share what works for me. Don't give up, because there's nothing like starting seeds to chase away the winter blahs! I wish you the best of luck this year. :)

Thumbnail by KaylyRed
Everett, WA(Zone 8a)

Hi KaylyRed

Thanks for your suggestions! It sounds like you have graduated to "success".

Are your shop lights 2-tube or 4-tube? Standard flourescents, T8 or T5?

When do you pop the sedlings out of the tary for potting up?
When the root have wrapped around the soil? Before they reach the edge of the cell?
As soon as there are four true leaves?

Is your room temperature close to 70 degrees? My house usually goes down to 60 part of the time.

The watering mat sounds very promising: if I order anything from Burpee again, I'll get one 'replacement mat' so I know what the material is, and can look for a cheaper source.
Does one end hang down into a water supply?

I also agree that "deeper cells" sound promising, but those were sold out where I looked last year. What size cells do you use, like how deep and how many per 11"x21" tray, and for what kinds of plants?

The insert and plug trays I do have tend to be only 2.25" deep.
- - 606 Jumbo - 6, 6-paks = 4x9 cells = 36 cells
- - 1801 Deep - 3x6 cells = 18 cells (3.5" deep??)
- - Square Plug Tray 50 or 72 Cell "TLC Pro Plug Tray, (2.31"deep?)

These is where I shop, for the "Hobby Packs" of ten trays at around $1 per tray.

What seed starting mix do you buy? I'm disenchanted with the Joffy Mix I always used, becuase it seems like pur powdered peat, and gets very soggy and seems not to drain or let much air in. I've been adding sand, perlite, "Orchid Mix" or various kinds of shredded and screened pine bark to get some aeration and drainage.


Watertown, WI(Zone 5a)

Hi Corey,

I'll try to answer your questions...

Are your shop lights 2-tube or 4-tube? Standard flourescents, T8 or T5?

They're just standard fluorescents. 2 tubes. I buy the tubes that are supposed to emulate daylight. (In fact, I think they say "daylight" on the packaging. Sorry I can't be more helpful there as to brand/type.) For flowering plants and my herbs, which I've transplanted to bigger pots, I use one bulb labeled for "cool" light and one for "warm." Seems to me that it gives a fuller spectrum. Can't tell you the results there yet, but so far it looks promising.

When do you pop the sedlings out of the tary for potting up?
When the root have wrapped around the soil? Before they reach the edge of the cell?
As soon as there are four true leaves?

I've potted them up as soon as they have a couple sets of true leaves without any issues. And even then I find that the roots are long and already reaching the bottom of the cells. If you leave them longer, they do get much more root bound. (Not that that's necessarily a bad thing with these plug-size seedlings.) They do get harder to remove from the cells without roughing up the roots the longer you leave them.

Is your room temperature close to 70 degrees? My house usually goes down to 60 part of the time.

Usually. And my seedlings are near a heat vent, which is why I like the Burpee setup to help me keep things from drying out. Our house is set to go down to 55 at night, so my seedlings get cooler evenings, but since cooler evenings emulates nature I really don't worry about it.

The watering mat sounds very promising: if I order anything from Burpee again, I'll get one 'replacement mat' so I know what the material is, and can look for a cheaper source.
Does one end hang down into a water supply?

Yes, the mat rests on a tray that has four "feet." The ends of the mat sit in the water supply. I find I need to top mine off about once a week to keep the mat moist and wicking water up to the seedlings. I water between the cells bottoms directly onto the mat and let the runoff stand in the basin and continue to wick up.

I've seen the Burpee Ultimate Growing System at Shopko recently for $15. I think $15 is about as cheap as you'll find it. I only have two of them due to their price, but I plan to add another this year. Honestly, I prefer them to other types of flats.

I also agree that "deeper cells" sound promising, but those were sold out where I looked last year. What size cells do you use, like how deep and how many per 11"x21" tray, and for what kinds of plants?

These are 2.25" deep, and there are 72 cells to a tray. (I think they come in a 36-cell size, too.) They narrow at the bottom. I do wish they were deeper than they are, but I like the way they work overall. With flats (the kind that don't have cells) I notice that my plants don't seem as well-rooted as the plugs in the cells. Maybe it's just me, but...I think there's something to it. :)

What I like most about the Burpee system is the watering setup.

What seed starting mix do you buy? I'm disenchanted with the Joffy Mix I always used, becuase it seems like pur powdered peat, and gets very soggy and seems not to drain or let much air in. I've been adding sand, perlite, "Orchid Mix" or various kinds of shredded and screened pine bark to get some aeration and drainage.

I've been using Stein's Garden Center's seed starting mix. It's okay, but I wouldn't mind better. This mix is mostly peat moss, too, with vermiculite. This year I've been noticing a bit of green mold on the soil surface with my coleus starts, but it doesn't seem to have affected germination or growth at all. If those soil tablets from Burpee weren't expensive I'd buy them again--I'm not sure what they contained, but I liked them better than the starting mix I have now.

Hope this helps!

Everett, WA(Zone 8a)

Thanks very much, KaylyRed!

I'm right with you on when to pot up, in theory, but somehow I usually seem to let them go until they are too root bound.

I will definitely start looking for that kind of mat, and will post here if I find deeper trays with more than 18 or 36 cells.

I've heard the suggestion of sprinkling "chick grit" (or maybe very clean, coarse sand) over top of the cells, to reduce mold and algae. The author of "Square Foot Gardening" suggests vermiculite, but that might be mainly for outdoors. (he doesn't use bark or sand, but does use chick grit).


Columbus, OH

To nick seed without a potential visit to the ER, use toenail clippers to nip a bit of the seed coat. Works like a charm, and no gouges on your fingers.

(Pam) Warren, CT(Zone 5b)

I'm late chiming in to this thread, but I have a comment about the Burpee system, which I tried last year. At first I was excited to find it and bought a few. I used to use APS, which is similar but sturdier, and got used to the capillary matting. I swear by this type of system. But I did have a problem getting some of my seedlings out of the cells. Granted, they were the weaker ones, but in the past I've been able to do it without killing them or destroying the flat. Also, I soon switched to regular seed starting mix. The pellets floated up and fell over sideways when I added water. That made them too compacted to use and were a nightmare to fix.

Later in the season I discovered larger, sturdier container, platform and capillary mat setup from Gardener's supply- no cell packs or clear plastic covers, but I have plenty. So this year I'll be using a combination, depending on what I'm planting and when.

This year I bought a seed germination station from Parks on sale...mainly because the set was cheaper than you can buy just the mat, and I needed another one...I seem to do more every year! To my surprise the cell setup was very good...72 cells, and deeper than average. It's in one piece, and I have already cut it in half. I agree it's much easier to deal with that way, did the same thing with the ones from Burpees.

So good luck to us all...

Sierra Foothills, CA(Zone 8a)

Quote from Pfg :
I'm late chiming in to this thread.....

This year I bought a seed germination station from Parks on sale.....It's in one piece, and I have already cut it in half. I agree it's much easier to deal with that way, did the same thing with the ones from Burpees.

Pfg ~ What part did you cut in half?

Watertown, WI(Zone 5a)

Pfg - Funny how people's experiences will vary. I've read reviews of the Burpee seed starting system where folks complained about being unable to easily remove seedlings from the cells. I use a metal dinner fork, work it along the side of the cell, and the seedlings pop right out for me every time. Then I carry them right on the fork to the hole I've already made to pot them up or plant them out, whichever I'm doing.

The Burpee cell flats are actually already cut in halves of 36, but you have to sort of flex them to pull them apart. Unless maybe the older ones were all one piece and I have a newer version.

Either way, though, I do love the mats. Even after I transplant I keep them up and use them to bottom water my larger pots. Works well with plastic pots, but it was an awful mess when I tried to use coir and peat pots. ;)

(Pam) Warren, CT(Zone 5b)

Evelyn, the cell flat from Parks comes in one piece, as did the Burpee ones I got last year. I found them inwieldly to deal with, hard to move around, and don't always want 72 of the same thing. So I cut between the rows to separate them into 2 or 3 separate pieces. That made it easier to keep track of different plants and give them more or less light and heat or even start hardening them off as they grew.

KayleyRed, I had lots of puny little things last year because of the huge damping off problems and re-sowing. Their roots didn't hold tne medium together, and/or some were horribly compacted because of falling over sideways when I wet them and I had missed fixing them before planting and sometimes when pushing up from the bottom the cursed flimsy cell crumpled and mutilated what roots there were! Most of them- the ones I didn't kill getting out of the cells, eventually got going in the garden, but later than I would have liked. That's why this year I'm starting some things so early. For one thing, I'm determined to have petunias for my hanging baskets that look like the nice full ones you can buy in May instead of teeny little guys spotted around in a sea of brown.

I agree about the capillary mats, completely rely on them. I've sometimes had to leave seedlings untended for up to 10 days, and the water has lasted. This year, though, I won't leave the heat mat on when I have to be away, I've learned that lesson the hard way!

Sierra Foothills, CA(Zone 8a)

Quote from Pfg :
Evelyn, the cell flat from Parks comes in one piece, as did the Burpee ones I got last year. I found them inwieldly to deal with, hard to move around, and don't always want 72 of the same thing. So I cut between the rows to separate them into 2 or 3 separate pieces. That made it easier to keep track of different plants and give them more or less light and heat or even start hardening them off as they grew.

Pfg ~ Thanks! I might try that next year. For this growing season I have already expended my alloted budget so the "germination station" which includes a heat mat, as well as two other heat mats and various cell packs with bubbletops will have to do along with what I started out with last year - plastic fruit containers which already have drainage and holes at the top as well, initially covered with translucent produce bags. I will also W/S into some one gallon nursery pots and maybe 4" as well. I'll see how far I get. This is just my second year into "full-bore" seed-sowing.

Springfield, IL(Zone 6a)

I've been busy elsewhere but have finally caught up here again. Thanks again for such great help! I wanted to ask some more questions if I may.

1. You all seem to agree that plastic divided cell trays are the best.
2. The depth should be 2.25 inches or a bit more if possible.
3. I can water from the bottom and avoid the problems of last year.
4. Celene- I love the tip about scoring the seeds with toenail clippers- I used a knife last year! :)

1. Where is the most cost effective place I can purchase the trays?
2. I have a couple of heat mats- do I just place them underneath and rotate them as I did last year?
3. Are the trays you are discussing covered with the clear plastic lids I've seen?
4. Corey- did you find what everyone was talking about for less money???

Thanks again!!! :)

BTW, KaylyRed, my parents live in Watertown and I come up semi-frequently. I LOVE those perennial places in WI that are mom & pop places. My mom and I go and get great plants with quite a few in a pot, divide and share them! :)

Everett, WA(Zone 8a)

Hi SusieR

I haven't found chick grit yet, and since have heard of coarser "turkey grit". mainly I;ve been busy with work. But I may fall back on dirty old coarse sand. Meanwhile, i just used up the rest of my Perlite

I still like these places for trays of inserts, like 72 cells per tray, 36, 42, 50, 98 or 128.
Especially Greenhouse MegaStore. I get the "Hobby Packs" of ten trays at around $1 per tray.

I have two of the clear covers, and like them. But after those two are in use, I will cover a tray with "Saran Wrap" and that works fine, since we have to take it off anyway as soon as sprouts emerge.

It will droop over the cells, and rest on he soil if the soil goes right to the top of the cell (which i rpefer, to get more soil depth). If you sowed seed on the surface, you might worry that the seed will cling to the film and be pulled away from the soil or moved around. But using strips of mini-blind slat plastic as labels and supports hold film away from soil, like short tentpoles.

I happened to buy an 18" wide roll of plastic film from a restaurant supply store or a place like Costco or Sam's Club. That is easier to use and be sure of a good seal to keep humidity in, but I imagine that noraml saran Wrap can do the same thing, especially if you use two strips. My 18" roll should last the rest of my life. I should will it to someone in nDG, but postage would cost as much as the roll!


Galesburg, IL

1. I've found that the best place for buying 1020 flats, inserts and any other associated plastic container is the Greenhouse Megastore they sell all of these in "Hobby Pack" sizes of 10 pieces. They are the cheapest I have found anywhere and are extremely fast with shipping.

2. I use heat mats under the flats that need warmer than ambient temperature for optimal germination. I keep my heat mats on a thermostat and they are only used for germination. Once plants are germinated, I move them off the mat to cooler temps.

3. I keep the plastic domes on during germination and remove them once germination is complete. If the lids are accumulating a lot of condensation, it is too wet and I will remove or vent the lids to help remove some of the excess moisture.

4. Because of the number of plants that I grow each year, I would never pay for any of the "system" kits sold by many seed companies. They are very expensive unless you are only going to grow one or two flats of plants. For the price for one or two of those kits, I can literally grow hundreds of plants using generic trays/inserts and peat based potting soil. If I were going to start from scratch, my cost per flat of plants (excluding seed) would be roughly $1 for the tray, $0.80 for the inserts, $1.25 for the plastic dome (which will be used on multiple flats) for a total of about $2.25 not including the planting media. Additionally, I will reuse all of those for between 3-5 years. For the cost of 80 (40-cell) "sponges" I can purchase enough peat, perlite and lime to mix my own media and grow about 1200 seedlings with enough media left over to fill a couple of flower pots for my deck.

I understand the allure of these all inclusive kits for the beginning seed grower, those growing only a few trays of plants or those who need the wicking systems when they are away, but with a little knowledge you can save a lot of money (or grow a lot more plants : ).

I am not trying to discourage anyone from buying those kits if they fit your needs. I just want everyone to know that there are alternatives especially if you want to expand your seed growing and cost may be an issue.

Everett, WA(Zone 8a)


I also cut down my "insert trays" At first it was just so that I could more easily turn them over and tap them, or push on the bottoms of cells to pop the rootballs out. I was squeamish about digging in there with a knife or fork, but I guess I'll try that this year.

I find, even with trays of 128 "plug" cells (16 rows, 8 cells per row, with no perforation), that I can cut them so that each chunk has only 2-3 rows of cells, and they still stand up. Then, if one batch of 16 or 24 seeds sprouts much sooner than the rest, I can remove them separately and easily pot them up.

While thinking about using tiny "wicks" (instead of well-draining soil mix) to help drain excess water (or "perched" water) out of shallow cells, or assure that bottom watering will reach the soil in each cell, I thought of a side-benefit to threading a small wick into each cell, so that it runs up from a drain hole, through the soil column, over the top and down into the next cell.

When I'm ready to pop plants out of the cells, even if I'm still reluctant to jab the roots with a fork, I could cut the wicks below and between the cells, and use them like little string handles to PULL the root balls out of the cells!

A solution without a problem!


Springfield, IL(Zone 6a)

Is this the right thing to order?
50 TLC Square Plug Tray 50SQ CN-PLG050 5 x 10 2.38 2 1.15 6.4 302

These are the deepest ones...

OR, should I be getting the "Traditional Inserts?" If so, what size/configuration?

I have a couple of lids and mats for heat and I think I'll stick with the lights I have b/c of cost right now.

You mix only peat, pearlite, and lime for your growing media??? What ratios do you use? I'm surprised by the lime unless it's not much...

Columbus, OH

Susie, if your plants don't have enough fluorescent or natural light, it won't matter what flats they're in, they won't do well. The incandescents just don't have the right spectrum. My fixtures were $10 each at one of the big box stores. I use newspaper pots in regular flats--they're free :)

Everett, WA(Zone 8a)

>> the right thing to order?

Well, a 50-cell tray has slightly bigger cells than a 72, and much bigger than 98, so that sounds good to me (a beginner). My only 50-cell tray has round cells, and seems deeper thazn some other inserts, and I like that, too. They are like small Dixie cuops, except they don't fall over.

Mostly, I have little idea which kind is better for what purpose. I've been going by trial and error, and learned that "shallow" and "small" mean "re-pot very quickly". When I'm in doubt, now, I tend to use a 72-cell insert tray for annuals or anything I hope to move directly from a cell to the garden. The 50-cell t4ray might be even better for the plants, if it gives them more soil.

Probably smaller cells are more for holding as many seedlings as possible until you re-pot hundreds into bigger pots. But I'm guessing!

I would also love to know from someone knowledgable the tradeoffs among different sizes and shapes of cells or inserts. Round, square, tapered, "vented" ... what kinds are best for what use, and why?

There seems to be a fundmental difference in application for "plug trays" and "inserts".

Inserts seem always to be tearable into 6-packs or 4-packs, and are flimsy or floppy so that they need to sit in trays that support them. Are they "tearable" so they can easily be sold separately? Or so they are easier for hobbyists to take out to the garden a few at a time for planting directly into soil from the inserts?

I tentatively think that "plug trays" are more for pro growers, who start thousands of seeds in the very smallest possible space and amount of soil. I think they may be designed for automated handling equipment without needing a separate tray under them to hold water. "Plug Trays" always seem to be much more strudy, have no perforations, and have small cells that will need to be re-potted very soon.

Maybe they are designed more for perenials, or even trees and shrubs, than vegetables and annuals??


Galesburg, IL

The size of cells you use depend on the type of plant and how long you are going to keep plants in them. Inserts can easily be torn apart into four or six packs. Plug trays are meant to be handled as a unit although you can tear them apart if you really want to, but that kind of defeats the purpose of the tray. Unless you plan to plant a whole tray of the same thing I would stick with the "inserts". I keep a tray under both inserts and plug trays for support and to keep soil/water from draining/spilling on the floor or onto other trays of plants (I use a homemade light/rack system that only uses PVC pipe to support the trays). Both trays and inserts can "stand alone" without a tray if you don't mind the mess underneath them.

Now as too shape and size of cells. I'll list what I use/do, but don't take that as gospel, everyone seems to have an opinion as to what is best. The smallest cell I use is the 128 plug flat. I use these only for things that I need a lot of and for things that are VERY similar in their germinating needs. Primarily I use the 128 for onion transplants (four trays this year) and for some perennial plants that need stratification before germ. I leave the onions in the 128 trays until they are transplanted into the garden at about the 3-4 leaf stage. I use them for stratification of perennials because they hold a lot in a small space. I am a believer in one seed/one cell, so I will only use the 128 trays for those things I know have a high germination rate. The perennials I grow will be transplanted from the 128 trays into 2.5 inch square pots for further growth before transplanting. I do this to get as much root growth as possible on the perennials.

Annual flowers will be started in either 72 (1206) or 48 (806) cell trays. If you haven't figured it out yet, the numbers of the cell packs refer to the configuration of the packs in a 1020 tray. I.E. a 1206 cell pack has 12 packs of 6 cells per standard 1020 tray and an 806 has 8 packs of 6 cells. All my annual flowers will stay in the packs they are started in until transplanting. The exception is some of the very small seeded flowers (lobelia, petunias, ect) which I start in 4 inch square pots and then transplant into 806 packs. A side note: I know that many people constantly repot their plants as soon as they start to see roots coming out the bottom of the cells. I don't worry about that probably because I don't have the time or space to repot everything into larger pots. As long as you tear up the root ball well before planting them in their final spot, the plants will be fine. They may be set back a week or so from something that had been grown in a larger pot, but I have never had a plant die from being root bound in a cell pack. (Look at everything you buy commercially - they are almost all severely root bound and survive just fine).

I grow all my vegetable plants in either 806 or 804 cell packs with no stepping up to larger pots. Cabbage, cauliflower, broccoli, Brussels sprouts, peppers, tomatoes all get seeded into these and stay there until they go into the garden. I tend to use the larger cell packs for tomatoes and peppers and the smaller ones for the cole crops. This is not a hard and fast rule, and often I just use the first thing I grab when seeding them. If you are only going to grow a couple of flats of plants, don't think you have to buy several different sizes of cell packs. Base your decision on the number of plants you want to grow in the space you have. Most plants will grow just fine in 72 cell packs until they are ready to transplant (or 48 or 32 cell packs). I would not grow things in anything smaller than 72 cells unless you plan to transplant them (with onions and a few others as exceptions). A few years ago when I worked at a research farm/greenhouse we grew all tomatoes in 72 cell plug trays from seeding to field and never had any problems. The one thing that you will need to monitor closely is watering if you grow larger plants in smaller cells. As the plants get larger, you may need to water them at least twice a day!

I grow everything in cell packs/trays that are "square" sided. I think that plants get much worse root bound in round cells.

Many plug trays are designed for automated handling in larger operations, but they will work just fine for the small grower/home gardener if you need that many plants of a particular type.

Soil media - a couple of years ago I started mixing my own seed starting media. I couldn't find a good source locally for seed starting mix and I didn't like the consistency of the potting soils being sold. A few years ago I notices that many potting mixes were getting away from being primarily peat based and were using a lot of composted "forest materials" in their mixes. I found a lot of this "compost" was not fully composted and found everything from large chunks of bark (>1 inch) to rocks and lots of plastic/fiberglass threads mixed throughout. In addition, I continually had problems with fungus gnats and a lot of surface molds with mixes from all the major manufactures. I started to look at the composition of various seed starting mixes and found that their primary ingredients were peat, perlite and or vermiculite, with some level of lime and nutrients mixed into them - very easy for the home gardener to mix themselves. The one thing they did have that is difficult/very expensive to include is a wetting agent - I couldn't find an economical way to include this in my mix, so I don't.

The mix I use is very simple - screened peat, add perlite until it looks good and then add 1.5 tsp of pelleted or encapsulated lime per gallon of mix. I add the lime because peat is very low in pH and can inhibit some plants growth. I haven't done any tests comparing the addition/absence of lime, but it makes me feel better and doesn't hurt.

I buy compressed bales of peat, break them up and screen it through 1/4 inch hardware cloth. Add perlite (more is better than too little although I have never measured the amount) and lime and mix well. I wet the soil and let it sit over night to equalize (also helps give the lime time to fully dissolve) fill cells/pots and plant. You don't need to buy/make a screen for the peat, just rub it in your hands to break it up and pick out any large materials. I just picked up a couple of bales of peat and paid ~ $6.50 for a 2.2 cu ft compressed bale. Small bags of perlite go for around $3.50 and it will probably take around 3 bags of perlite for the bale. I've never actually measured how much mix I get out of a bale of peat, but if I had to guess, I will get around 20-25 gallons of final mix from a 2.2 cu ft compressed bale. I'll let everyone do the math and compare prices to purchased mixes.

Seeds don't need any nutrients to germinate, and in fact can be hurt by high nutrient levels in media, so I don't add any fertilizer to my mixes (perlite does have a small amount of fertilizer impregnated on it, but this is not a problem). I fertilize when I water the plants, but you could very easily add encapsulated (time release) fertilizer to your mix if you wanted.

You can find recipes for various seed starting mixes through Google.

Everett, WA(Zone 8a)

Thank you, trc65, I greatly appreciate your experience and givng your reasons for each choice!

I started a whole new category in my notes.

new to me was
- it's OK if they get somewhat root-bound
- move petunias from "4-inch-flats" into 48-cell 806 cells. Last year I went from round 98-cell plugs to 72-cells
- make seed mix from just peat and perlite - you must be using lots more Perlite than I ever did!

Every peat mix I've tried becomes a soggy sponge. I tried adding perlite and sand 9not enoguh Perlite and too-fine sand, I think. Up until now, I also blamed "too much peat", when maybe the problem was 'watering too much'.

This year I'm using pine bark fiber and chunks, lots more perlite, some very coarse vermiculite and just a little peat. I'm trying to decide whether to add dirty old coarse sand, or take time to shop for chick or turkey grit, when I'm already behind in WS, indoor sowing, and at work!


Springfield, IL(Zone 6a)

This is great- thank you so much!!!

I have to get my seeds together and order the trays. I am going to list what I've bought and then ask for some help thereafter. I have some more questions...

1. Are the 20-cent seed packs from Wal-Mart, etc. any different than the $3.00 seed pack of the exact same plant? If not, why?

2. What is the best source for seeds online in your opinion? (Value/quality)

Lastly, I don't use plain incandescent lights. I bought clip-on silver "shades" in which I put grow light bulbs. From what I understand, grow lights are fine for seedlings. I agree that the florescent fixtures are better but I don't have those yet. We were actually told that, when using the two tube florescent fixtures, you should use one "soft" white and one "daylight" white because that gives you the full spectrum of light without the cost of the special grow light bulbs for the florescent fixture.

Everett, WA(Zone 8a)

I have used the "pretzel" compact flourescent bulbs screwed into normal incandesent fixtures.

I think Wal-Mart seeds are about the same as any, just smaller packs and commoner varieties.

>> What is the best source for seeds online

DAVE'S GARDEN SEED TRADING FORUM! No question. Ask and ye shall receive.

There are other websites where people trade and give away seeds, but as a courtesy to DG Admins, we don't speak explicitly of them here.

For example, with DG Seed Trading Forum:
Free Seed for Newbies!11/18/2010 Directions to get your seed

And on any thread, if you mention that you're just starting out growing from seed and want to learn to save seeds, many people will just send you seeds out of gardening generosity, or send them in return for postage and a bubble mailer. (Maybe buy two dozen bubble mailers and offer to trade those plus stamps for seeds.)

You might browse the threads in the seed trading forum, and look for people who have things you want. Then look at their "Want List" by double-clicking on thier name. Dmail them, and offer to buy them a pkt of something rare that they want, if they send you a few common vegetable or flower seeds that you want.

Or go to a place like Hazzards that sells very big packs at wholesale prices (1,000 or 2,000 seeds), split each pack into 10 "trades" and start a thread offering to trade what you have for what you want. I'm betting that half the people who respond will toss in extras and just encourage you to share with others after YOU start saving seeds.

for fancy or rare seeds, i like these: Asian vegetables, great variety and big packs GREAT variety, and $2 shipping for 5-6 packs ... from Belgium! Jonna is great.

Someone reccomended this, I think because they have small, inexpensive packs, yet enough for small gardeners toi try the seed out:

Lately I have not been wanting to buy from the "big name big catalog" vendors, at least the ones that would rather sell hybrids and mixes so i can't save seeds, or give ambiguous names that sound like new, proprietary varieties but anren't. but I do feel as if I owe them something for the beautiful color photography they send me every year: like Playboy for gardeners!


Galesburg, IL


I would stay away from using sand in your planting media as a drainage aid. When I have tried it in the past, it made a very dense hard mix that I felt was too heavy and hard for roots to penetrate. If you are looking to lighten up your peat mix, I would stick with perlite or vermiculite. If you are looking for sand to top dress your seeds (instead of the chicken grit), you might look into getting some silica sand that is used for sand blasting. That is what we used to use at the research farm I worked at. Unfortunately, they come in many different sizes/grades and I have no idea what grade we used. It was however much finer than your standard sand box sand. I just mixed a batch of soil up this morning, and never even thought to measure how much perlite I added. If I had to guess, I would say I use about a pint of perlite for each gallon of peat.


There is another thread in the not too distant past that people list and discuss their favorite seed sources, both independent web only as well as larger commercial suppliers. You should find many different sources to satisfy your needs and budget. Just a note on using incandescent grow lights. Watch your temperatures closely, incandescent lights can get way too hot for young seedlings. Also, IMO using two different light bulbs for the florescent lights is unnecessary. Young seedlings need light primarily in the blue spectrum which corresponds more to the cool white bulbs. The blue light contributes to leaf formation/growth and well as good chlorophyll production. Light in the red spectrum is needed more for reproduction and flowering (warm colored lights). If you are going to use the lights for seed germination/early growth, cool white bulbs are all you will need. If you are going to use the lights year round for indoor plants/flowering, then use one cool and one warm bulb. I only use my lights for seedling growth so I only use cool white bulbs. If you do a search here, there are several threads that talk more in depth about light sources, hours of operation needed, etc.....

Everett, WA(Zone 8a)


I agree that sand makes any mix heavier. I can't speak to root pentration because either soggy mix or heavy, hard mix prevented good roots.

(Coarse sand does make my clayey soil more friable ... but I don't use the clay on seedlings. I've also learned not to use any kind of potting "soil" until I find something less gooey and gluey.

>> If I had to guess, I would say I use about a pint of perlite for each gallon of peat.

Hmm, 1:8. I've used that much medium or fine Perlite, and maybe it would have worked - maybe I was just starting too wet and then spraying the surface too often.

Ideally, I would like to see water come out the bottom if I over water the top.
Right now, it SEEMS like a one cubic inch cell is tenaciously holding two cubic inches of water!
And I wnat to create an open enough texture that there are more air-filled spaces than water-filled spaces.

This year, I bought 8 quarts of very coarse Perlite and liked it, though I used it up quickly for aerating fine bark fibers and a little peat. (I'm still hunting for 1/10" - 1/4" pine bark CHUNKS or chips.)

Maybe I'll try a mix other than Jiffy-Mix for my peat component. That seems milled down to peat powder. Better yet, I'll do as you do, and buy a bale of peat then screen it gently so the fibers stay longer. And maybe try some coir again, now that I know to flush out salts before using it.

I'm still adding your tips to a new page in my garden notes, under
"Garden Propagation notes Starting Seeds - Germination"


Augusta, GA(Zone 8a)

I am growing from seed the second year. I use some trays to sow seeds in a moist soil. I covered it with plastic film and the seeds are coming up, when do I take the plastic of so it wont be so much condensation. Can somebody help please? Up till today I have planted some salvias and agastaches,.

(Pam) Warren, CT(Zone 5b)

The plastic should come off once you see germination. Some say to leave it partly on for a couple of days, closing it at night. Once the plants get growing their roots go down into the soil and get the water they need there. At that point it's better to keep the surface less wet and water from the bottom to avoid damping off, among other things.

Good luck! Pam

Augusta, GA(Zone 8a)

Thank you very much, you are a great help.

Watertown, WI(Zone 5a)

I take the plastic off as soon as the first set of leaves (the cotyledons) has emerged. The plastic is for moisture retention (hence the condensation, which is actually fine and helps keep things moist and warm as the seeds are emerging), but keeping it on too long can lead to fungus problems.

That said, sometimes you have to wait for some slow starters in a flat, especially if you've planted different types of seed. I keep the flats covered until I think most everything in them has emerged as long as the seedlings are looking healthy under the plastic, and I try to only plant seeds with similar germination rates in a single flat.

Augusta, GA(Zone 8a)

I have not mixed my seeds, it said that it will take 2 weeks for agastache, it showed green after a week, but the salvia is slow, so I will wait to remove the plastic till after two weeds. The seeds were so small, it was hard to spread them out so I will see how I did. What is the best metode to sow seeds that are so small you can hardly handle them. I tried with tweezers, but ended up just handleing them one at the time from a white sheet of paper. Thaks for your advise. The petunias are small to, that I will do next week.

Galesburg, IL

kiseta, they way I handle very small seeds is to fold a piece of paper in half, put the seeds in the crease and tap the paper to distribute the seeds either in rows or around a pot.

Watertown, WI(Zone 5a)

Same here. I wish more tiny seeds came in pelleted form. I got petunias, pansies and some coleus in pelleted form and loved it.

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