Has anyone used soil blocks?

Spring, TX

Has anyone used soil blocks successfully? I've been doing some reading about them online, and seeing lots of praise. I love the idea of not using plastic pots to start seeds! But I consider everyone here to be the experts though, and don't remember ever seeing a discussion of this method. It looks to me like the blocks would fall apart when you water them. There are several places to buy them, but also several sites giving instructions on making them. I love the idea of not using plastic pots to start seeds! Here are a couple of places I was looking:


Nederland, TX

Hello nearby Spring! Yes, I use soil blocks and love them! You can go online and find out soil recipes that work well or you can order soil already mixed which works well with soil blocks. Johnny's Selected seeds has a good mix. Go to their site and check out the soil block makers and the soil. If you water carefully the bottom, there is no crumbling problem. I put mine in a standard no-holes flats and have no problems. Great transplants with no shock.

Arlington, MA(Zone 6a)

i bought soil block maker, and some soil mixes, just so i know what the mix should look/feel like. (i don't plan to always have dirt shipped across the country!) i will try to report back in march/april.

Brighton, MI(Zone 5b)

I'm not sure about their performance yet because this is my first time seeing them, but they are under the brand name "Jiffy", which is part of the Ferry-Morse seed co. It's a self-contained germination kit with tray, lid and peat pellets. The pellets swell with water and are held together with fine netting. I paid $2 for the 12 pellet, and I believe the 25 pellet kit was $5. I got mine at Meijer, but I would think that Wal-Mart and Home Depot, etc. would or will carry them.
I hope they work well not having perlite or vermiculite, but the kit is convenient and cheap. They sell just the pellets as well. I think 25 were $3. Trial and error. Just thought I would share that if anyone is interested in trying them.

Storrs, CT

I am going to try soil blocks this year for the first time. I am also using cowpots. Im going to compare them. something tells me that just using the cowpots will be much easier... but we will see.

I saw on martha stewart... I know... that Vermont Compost potting soil works really well for soil blocks.


This is where I found it online. Not many people sell it. The NOFA people love this stuff. I'm hoping I will too.

This message was edited Feb 1, 2012 10:11 PM

Arlington, MA(Zone 6a)

fedco also has Vermont Compost potting soil ( Fort V) for soil blocks. i love fedco (in Maine).
i am looking around my area to source my future materials locally to save on shipping.

my first blocks i placed on a wicking fabric since i hope to be able to set up a wicking situation for when we go away. i made the fabric too wet, and kept the blocks too wet for about a week. i was afraid the blocks would dissolve. but i set up a fan on them for a day and they firmed up very nicely. i could even move them around a bit. it's good to know the blocks are not as fragile as they would seem, since we will all make mistakes getting used to them. i will do more blocks this week.

Carmel, IN(Zone 5b)

I'm watching this thread to see how everyone's results are using the soil blocks. I'd love to find an alternative to the cellpacks I use every year.

There was a fairly extensive account of using soil blocks in the Tomato forum


Brighton, MI(Zone 5b)

I'm curious as well to get into making my own blocks.
The "Jiffy" brand peat pellets I mentioned earlier are working well though. I've got some very healthy tomato seedlings going and some bell pepper seedlings on their way. I have to admit that they are very easy to use and self-contained with no worries of them falling apart. The only drawback I can see with these is that obviously the composted manure mix would have more nutrients to start them off. I'm hoping to compensate for this by transplanting into my own compost and adding fertilizer as they grow.
As this would not be much of an issue for ornamentals, these are a great way to go.
I must admit that almost $40 a bag w/shipping for a 20# bag of the manure mix is a lot right now too. Maybe I can find it locally but, it will probably be too late in the season.
Good luck all.

Arlington, MA(Zone 6a)

so far so good on the soil blocks. findings:

- the mini's do quite well on the wicking fabric. you have to watchful about the roots growing into the fabric.
- the mini's with mustard greens were ready to be "blocked up" in about 10 days! i didn't know it would be so quick.
- i have made a mix with about half consisting of "coast of maine" potting soil, readily available around here. i just need to devise the entire recipe. http://www.coastofmaine.com/soils-barharbor.shtml

Brighton, MI(Zone 5b)

I've got a question for you soil block users.
Are you relying on room temperatures to germinate and are you covering the blocks in any way for humidity factors?
Some heat may be generated by the breakdown of the organic material in your mixtures but, in such small quantities, it seems minimal. Just wondering on your germination success rate with this method.

Arlington, MA(Zone 6a)

i germinate in my living room, so temps never get below 63, and are often 65-68. i cover the blocks until they germinate. sometimes i put flats on top of a lightstand fixture, for defacto heat mat action. (mustards were up in 2-4 days with the "heat mat")

i keep my miniblocks on a wicking fabric. the 1st batch i did, pansies, i kept the fabric just TOO WET. i stratified them for a week that way. once dried out, i got 50% germination, old & new seeds.

since then, i have got these germination rates -- in the not too wet method.
- 2nd batch pansies, stratified 1 week : new seeds 16/20. older seeds (2010) 13/20.
- mustard greens: 17/20
- snapdragons, stratified 1 week : 33/40

This message was edited Feb 27, 2012 10:27 AM

Brighton, MI(Zone 5b)

Thanks Seeder.
That's a pretty successful ratio. I was just curious if I got started into this method what to expect.
Thanks for the info.

Oak Island, NC(Zone 8a)

Soil blocks work pretty well, but I have switched over to using Oasis root cubes instead. I know they are mostly used for hydroponics, but they do go right in the soil with no problem. Using root cubes I get a higher germination rate and lose less seedlings.

Post a Reply to this Thread

Please or register to post.

Upload Images to your reply

    You may upload up to 5 images