damping off?

Coeur D Alene, ID(Zone 5a)

I have a problem: I had great germination for lisianthus and heliotrope seeds. However, they are both really little seedlings, and the lisianthus in particular barely have roots in the peat mix I'm using. In order to get the right amount of water on the top of the soil, where the roots are, I've been misting with hydrogen peroxide/water about twice a day. I missed one day of this, and all the seedlings dried out so I had to start over. But some of the seedlings look like they are damping off. Is there a better way to keep them from drying out?

Seattle, WA(Zone 8b)

Is it possible to bottom water them? Also mist them with Chamomile tea which will help cut down on the damping off.

Woodland Park, CO(Zone 4b)

The HP and Chamomile may help in the interm, but might want to cosider and then change cultural techniques that contribute to damping off.

Lower the temps by taking them off the heat mat if they are on one or lowinging the air temps in the room, decrease humidity by removing the dome if you're using one, bottom water and then let dry somewhat before watering again, and get some air circulation going.
Misting as the only source of watering will accomplish 2 things, not enough water with rapid drying of the soil mix (forcing more frequent watering than is necessary) and raises humidity which encourages damping off. Bottom watering is better and will not disturbe the small delicate seedlings, but you could also use a bulb syringe to water-not flood the soil or overly saturate it but you want evenly damp soil. Also, if you only wet the top of the soil the roots will stay there and have no reason to expand downward.

Boulder Creek, CA(Zone 9a)

caron ---

So seedlings generally do not appreciate being misted at all? I misted right after planting the seeds, and then just kept it up. I have mini-greenhouses and the 6-paks are very small, I thought misting was supplying enough moisture. Thanks for all the info!


Coeur D Alene, ID(Zone 5a)

Thanks for the info. It's stuff that I should already know, I just needed a little reminder!
I'm disappointed - I did an awesome job with germination - 90-100 percent, but I've lost alot of plants because they dried up or damped off.
So how strong of chamomile tea do you use? Would it help to bottom water with the tea for a couple times?

Seattle, WA(Zone 8b)

I use 1/2 strength around my house......I have heard others mention much more diluted works too.
It couldn't hurt to bottom water with some weak tea I wouldn't think :-)
Good luck with the babies you have left.


Waxhaw (Charlotte), NC(Zone 7b)

If you mist to keep the top 1/16" layer of soil damp you risk several things:

1. the water droplets settle on leaves. On small seedlings they may smoother the seedlings and otherwise the continued leaf wetness can be a contributer to disease.
2. the roots grow into the soil in search of water. If you mist the top layer of soil (deep it consistently damp) and the media below the top layer is not wet, you damage the roots, or prevent the roots from developing correctly.
3. a too wet surface will cause some roots to crawl on the surface instead of growing deep with some seeds.

Therefore, when sowing the seeds, let water soak up from below until the media is completely saturated/soaked. Then put aside to drain. Then - and only then - sow your seeds. Finally cover the seed flat with clear plastic and put under light (but not too close or the heat from the plastic enclosed flat will fry the seeds).

The plastic covered flat may not need to be watered again until germination. If the top layer of soil shows sign of drying ever so slightly, put the flat back in the pan of water and let moisture wick up from below again. This is the only really safe way to water seedlings.

Woodland Park, CO(Zone 4b)

Not saying that seedlings don't appreciate being misted, just that it's not the proper way to supply the water they need and can cause problems such as poorly developed root systems and disease. Sure, plants do appreaciate a misting/shower now than then, including seedlings. But it's not necessary for most common veggies and flowers.
Bottom watering with chamomile won't hurt and may be a little extra insurance while cultural techniques are being corrected. It just shouldn't be treated as the standard method to prevent damping off when the chance of disease is increased many times over due to poor cultivation practices.

Hamburg, PA(Zone 6b)

How about using a plastic cover?..Like a mini greenhouse...Just the cheapo plastic ones. I haven't watered my seedlings 2 weeks. As long as the fine mist is at the top of the plastic dome, I know there's sufficient water. They are growing and all is well with them.

Seward, AK(Zone 3b)

I broadcast seed in small containers then place them in 11x22" flats. I use starter mix that has been sterilized @ 180F for 1/2 hr. The starter mix is damp when I fill the containers, then I tamp it down to level it. I spray the surface with water, then plant the seeds. Small seeds are mixed with sand, particularly if they are to be surface sown.

When the flat is filled, I mist one more time, then mist the inside of the clear dome lid before covering. The domed flat is placed under closely positioned fluorescent lights until germination occurs. Seeds that need a higher temp for germination are placed on the higher shelves where the room temp is higher and where the lights from the shelf below help to heat the bottom of the flat.

When germination occurs, I remove the lids and begin watering from the bottom until ready to prick out the seedlings and transplant to cell packs. If there is any hint of dampening off, I add chamomile tea to the mister.

If the starter mix has been sterilized and the containers are all cleaned in soapy bleach water, dampening off is reduced to a minimum. Overplanting can contribute to both dampening off and spindly seedlings. My only complaint with bottom watering before transplanting is that water laden starter mix can make extricating heavy roots for transplant much more difficult. Chunks of the wet starter can cling to the roots. In a perfect world, I try to cut back on the underwatering before transplant.

Coloma, WI

How do you suggest to accomplish bottom watering?

Woodland Park, CO(Zone 4b)

With a tray underneath or in the bathtub or sink depending on how big the pots/flats are.

Hillsboro, OH(Zone 6a)

Rubbermaid/generic plastic containers work too. Just put an inch or so of water in the container, set in your flat or pot and let the drain holes suck up the water.

Seward, AK(Zone 3b)

If you're working with flats, they sell 11x22" flats complete with 12-6-cell packs and a plastic dome. The whole ensemble can cost around $4 if you look around. Two flats and one 4' shop light are a good beginning. Also, a bag of starting medium is a plus.

Oklahoma City, OK(Zone 7a)

Here's a link to help explain damping off and some control measures.


Osage City, KS(Zone 5b)

I've read alot of the posts and links and even googled on damping off..... The information talks alot about the area at soil level and the signs to look for. But I still have a question - I have some seedlings that are a little fuzzy around the area next to the soil.... The soil isn't moist and the leaves look healthy - is some fuzzy ok.... it doesn't look strange to me but this is my first year trying to start seeds..... Of course you all figured that out by my use of such technical terms as "Fuzzy" .... LOL

Seward, AK(Zone 3b)

VS, is it a fuzzy mold, or is it just the nature of the plant? What are you growing?

Osage City, KS(Zone 5b)

It looks like little fuzzy roots..... it's on the stem..... not the dirt..... does that help

Seward, AK(Zone 3b)

Some seedlings will develop little air roots above ground, particularly if they are quite moist and close together. Sadly, with dampening off, there isn't much warning. The stems will discolor at the soil surface, then the plants just tip over like little fallen trees. That doesn't sound like your problem.

Osage City, KS(Zone 5b)

I sure hope not ..... but I suppose if there isn't anything I can do about , which sounds like the case in all I've read, then it's just wait and see anyway...... Thanks Weezingreens for the info...... I'm trying really hard not to overwater but it's tough not to love them to death......

Seward, AK(Zone 3b)

It's a tough row to hoe, I'm afraid. That's why I like to germinate them in the covered flats, then remove the lids when they come up. I really think the key to avoiding dampening off is keeping everything sterile.

Osage City, KS(Zone 5b)

Am I past the critical stage when I get more than two leaves....? Does it do any good to try and remove the dying seedling from the cell pack in order to save the rest.....? or are they just doomed...? Thanks

I did start them in covered flats but I think I was overwatering so I'd removed the lids ...... I hope some survive...

Seward, AK(Zone 3b)

VS, If you wash all your containers in soapy bleach water, if you sterilize your seed starting medium at a temp of 180F for 1/2 hr, if you sow seed thinly and evenly, if you cover with plastic before germination, misting to keep moist, if you bottom water when germination occurs, removing the cover, you've got a pretty good chance of not having problems. All this has to occur in a warm area with very direct light. (Exception: some seeds need darkness to germinate, some seedlings need cooler temps after germination)

It all sounds complicated and impossible, but after a while, you get a feel for it. Removing failing seedlings from the container is always a good idea. You can also try adding 1 tablespoon of hydrogen peroxide per quart of water, or watering with weak chamomile tea. All these things are supposed to help prevent dampening off. However, once a plant is attached, it's terminal. Treatment helps to prevent its neighbors from falling victim to the same fate.

Osage City, KS(Zone 5b)

Thanks Weez,
As this is my first year at seedlings, I used all new containers and bought a mix - so I didn't think I needed to wash and bake the dirt - but I'll be sure and wash all my containers for next year..... I have been bottom watering - I think just to much is all ........

You are very helpful thanks for the advice.....

Bloomington, IN(Zone 6a)

I swear by weak chamomile tea, bottom watering, and maintaining air flow through use of circulating fans. Last year I used the tea and had almost no damping off problems. Prior to that, I'd had a lot of problems with damping off. I have also sprinkled chick grit (granite?) on the surface of my plant containers and I think this may have helped. Be sparing in your watering and don't mist.

Frederick, MD(Zone 6b)

All good advice!

FYI, here's a link to a recent DG article about damping off: http://davesgarden.com/guides/articles/view/277/

I alternate between chamomile tea and hydrogen peroxide added to the water... although once they've been potted up into pots or cell packs for a while, they're on their own unless I suspect a problem.

Chevy Chase, MD(Zone 7a)

Weezingreens: When you say to cover with plastic before germination, what kind of plastic do you mean? The plastic wrap that comes in rolls that you use to cover food in the refrigerator? I would have thought that would promote damping off by restricting air circulation.

's-Gravenhage, Netherlands(Zone 8b)

This is how I sow my seeds under cover: http://i208.photobucket.com/albums/bb270/AnkeFreese/Kraamkamer/kraamkamer2008.swf

Damping off doesn't often happen this way!

(Sheryl) Gainesboro, TN(Zone 6b)

Tuinkabouter, do you separate your seedlings out after they grow a bit? I was surprised to see how many seeds you put in one cup.

's-Gravenhage, Netherlands(Zone 8b)

Yes, I prick them out when I think their strong enough. I select the strongest, the weak ones I help out of their misery. I always put some extra seeds in because not all will germinate.
In the end I'll have 1-3 seedlings growing in one coffee cup, depending on their size. Usually I'll end up with 5-10 plants of each species, which is enough for my small garden.
After germination I remove the plastic bag and start watering them by pooring in the plastic tray. Never on the soil surface. I use water and sometimes chamomille tea. All this to prevent them from damping off. It usually works well!

Frederick, MD(Zone 6b)

Happy, regular kitchen type plastic wrap works just fine to cover seeds before germination... the trick is to take it off right away when you see a sprout, or prop it up and away from the seedlings and poke a couple holes for ventilation, at least.

Whether you're talking seedlings or cuttings, it's never good to have plastic touching leaves... it seems like that leads to condensation collecting on the plant surface, and that causes trouble with rot, fungus, etc.

Chevy Chase, MD(Zone 7a)

Critter -- that's exactly what I was thinking -- thanks.

Gilmer, TX(Zone 8a)

I've had mine hit the plastic and cause all kinds of problems. Usually death

Winnetka, IL

vs10799- your seedlings can definitely dampen off even after the second group of true leaves. I have an Oenothera that was on its third set of true leaves when it started damping off. I stopped watering it, and waited until the soil was pretty dry. By some miracle, it is still pushing growth. I assumed it had rooted above the withered part of the stem, but I don't see any roots. I expect it won't last long, and I'm treating it as an experiment. BTW, the base of the stem started withering over a week ago.

Seward, AK(Zone 3b)

Sorry for the delay in responding. I've been busy planting seeds, and I'm a bit behind! I purchased a case of the plastic dome lids for my holeless flats, but other things will work, such as plastic wrap. I like the dome lids because I can lift them off the flats easily, or even prop them up to introduce the air to some seedlings gradually. I mist the dome lids during germination and the droplets fall like rain on the germination trays. These dome lids also come in handy when I transplant some of the more delicate seedlings into cell packs. If they begin to wilt a bit, I can mist a lid and put it on the flat to give them some more time in a nursery situation.

Jefferson, GA(Zone 7b)

You all have probably already covered it but here is how I do it. I am not too sophisticated and am somewhat of a beginner but I just plant my seeds in the peat pellets in a tupperware storage tub thing covered with plastic wrap. Once they germinate and grow a bit, I pot up in these little tiny 10 cent pots I get from the dollar store. I put them all on one of those tin foil trays on the dining room table near a window. The tin trays are actually oven liners and they catch all the extra water at the bottom so if I forget to water, there is a bit of water in the trays for them to bottom water too. Not too sophisticated but I get good results. 80 to 100 percent. My only problem is waiting on the weather and if I get too busy I may get lazy about it all.

Columbia, SC

Weezingreens, do you start your seeds indoors? (I know you're in Alaska, but it sure seems like an ideal place for winter sowing~) Do you put any holes in your plastic domes?

I'm asking because this year I tried using one of those peat pellet-tray-and-dome set-ups. Problem is that some of the seeds sprouted, I kept the lid on hoping for others to catch up, and then discovered the dreaded damping off hit some of my Cosmos seeds. Waaah!

Guess I'll try the hydrogen peroxide solution...

Seward, AK(Zone 3b)

Hi, Fleurs. Sorry I didn't reply sooner. I was busy, as you guessed, starting seeds indoors! I've got about 18 flats of germinating and germinated seed trays down there now. I just had my DH, the Ol' Tomcat, turn on another rack of lights for me, as tomorrow I must begin transplanting my annual geranium (pelargonium) & artichokes to 3.5" pots., and when I do, one flat becomes four! I've had similar experiences to yours over the years as I went through my learning curve of seed sowing. I've learned to uncover the flats when germination begins... that is when I begin to see several sprouted plants coming up. While the greenhouse affect for sprouting is helpful, it does seem to cause problems once the plants start to come up. This is compounded if your seeds are thickly sown and the seedlings close together. I have to be particularly careful with lobelia for that reason.

I don't put any holes in the dome lids, as they are only on the flats for a short time. However, I do put the domes back on if the seedlings start too look like they are suffering transplant shock. In most cases, it is for a day, and I prop one end of the lid up with a pen or pencil or popcicle stick the second day to make a gradual change to the open air. Consider the domed flats as incubators.

Gilmer, TX(Zone 8a)

I'm tellin, I'm tellin. Old tomcat, what a name for your wonderful husband. And I know he's wonderful, cause they all are. lol

I can't believe all those trays. I'm using this lilttle bedroom with lots of light , but I only have room for 3 lights, (2 in each.) I think I'm watering mine too much, but they get so dry in those peat things. How dry should they be before I water. I'm talking about seedlings and small plants. I have some already trying to bloom. I just feel them and if they feel dry, I water, but maybe I watch too close.
Do you keep the trays with domes under lights. I do, but then someone said they didn't need it till they germinated
How long do I leave the plants under lights.

Don't you just love being the go to girl?

I started to move to Alaska once and we were all ready to go and then my Dad had a stroke and we didn't want to be that far away. Anyway, I know I really missed out.

Seward, AK(Zone 3b)

My DH became the Ol' Tomcat when I posted this thread: http://davesgarden.com/community/forums/t/213802/ We both get a kick out of the name... and he really is wonderful.

I start all my seeds under lights unless they are winter sown outdoors. There are a few types that need darkness to germinate, but I usually just put a piece of cardboard over the germination tray until the seeds break ground. Here's a great website for seed germination info: http://tomclothier.hort.net/

I moved to Alaska in 1974 from Indiana, and I've never regretted it. I can't imagine living anywhere else now. Of course, who knows how I'd feel if I'd gone to Texas first! It's all in the time and happenstance, isn't it?

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