Seed raising mix without buying products

Hey guys,

has anyone had success in making seed raising mix for annuals without buying products?
My homemade compost is a little sticky (like worm castings) so I add perlite to increase drainage and aeration. It works great but I want to avoid buying things wrapped in plastic. Is sand the next best option?

I have never understood the fascination with perlite when there is vermiculite around which is simply heated mica and provides minerals and  holds water, instead of being completely inert like perlite.

Sharp sand can be mixed with vermiculite and compost to make a really good seed starting medium.
The ratios are 1 part compost to 6 parts sand and 1 to 2 parts vermiculite if desired. The vermiculite will hold water and reduce the amount of times you need to water the seedlings once they are sprouted.

Many people simply use sand and mist about 4 times a day if uncovered, some folks like to use a cover to reduce evaporation at the surface.

Redhawk

Thanks Redhawk, very helpful

I don't see that the question was answered regarding not using purchased products to make the seed starting mix.  You still have to purchase sharp sand and vermiculite (although they may not come in plastic if you buy in bulk.)  I also would like to know a good recipe for seed starting mix that does not include any outside inputs.  I can make compost and dig up sandy clay "soil" or even go dig up some good soil from back in the woods.  But I would have to buy vermiculite or perlite or sharp sand, etc.

My seed raising mix is about 2/3 screened compost and 1/3 biochar. This is similar to my standard potting mix and works well...good balance between drainage and moisture retention, and the biochar aggregate helps to solve the shrinkage problem.

Donna Lynn wrote:I don't see that the question was answered regarding not using purchased products to make the seed starting mix. .

Maybe the answer is to just plant the seed in finished compost.  Maybe the OP compost is just not finished since it is sticky.

Or maybe there is just not an answer.

I prefer to plant my seed outside as I have much better results though I live in the sunny south.

Phil's biochar idea is a good one, that is something that can be made onsite (at least for me.)  I haven't tried making any yet, but if it works well combined with finished compost to start seeds, it will be worth it to give it a go.

I've been figuring this out for myself over the past few years, as well.  I'm in an aridland region, and the soil is extremely low in phosphorus plus compacts into a brick.  The good part is that the types of seeds found in the soil, most don't germinate at the same temps and rates as tame food plants.  So I can use the native soil for seed starting mix, if amended.

I'm trying to find a solution for the missing phosphorus without buying stuff, but I haven't yet. I've tried several things. Thus far, my most effective mix is:

Coconut coir - I buy one from Vermont Organics that comes in a cardboard box with no plastic.  You can get them from HomeDepot online.
Native soil - this is very sandy clay here, about the perfect proportion for making an adobe brick
Worm castings - I "grow" these now
Fish bone meal from Down To Earth.  This is for the phosphorus content. This has the lowest heavy metal/toxic mineral contamination of any phosphorus amendment I've found online.

I first mix the coconut coir and native soil about 50:50.  Then I add in some worm castings, which might take it to a mix of say 1 worm-5 coir-5 native soil?  I go by feel, but maybe notes here would be good for posterity, and sharing with others.  Then I add a little fish bone meal - maybe 1 cup to a 30 gallon tote of soil mix?

Also, I don't sterilize the soil. I desire the seedlings to be exposed to whatever is here in the ground. thus far, over three years, this has worked fine.  I've had damping off maybe twice (like two plants out of hundreds) but that could also be because of the drier environment, I suppose.

My worm castings contain a lot of coffee grounds, so I would have thought they'd have enough phosphorus to make up for the lack in the coco coir and soil mix.  Thus far, I haven't been able to with just worm castings alone, though.  Maybe I'm not using enough?  I've been concerned I would end up with too much nitrogen. This winter I will be trying more mix variations and see if I can get it to happen.

At least this mix above has worked really well.  All sorts of garden veggies start great in this mix, and so do herbs and native plants.  I grow out peppers and tomatoes very large in this mix before planting.

Kim Goodwin, if you have room for a pond you could grow your own fish meal (depending on how much you use - it doesn't sound like too much from your recipe.)  And if you have a greenhouse or can build one, you might be able to grow a dwarf coconut palm for the coir.  I have no idea how much coir you could get from one tree, but perhaps you could cut back on that in your recipe and maybe add some other type of dried plant matter.  Plus you get coconut meat and water!   My soil is sand and clay as well, although I am not in an arid region.  I hope to be able to produce a lot more of what I use once I am able to get my greenhouse built.  And a dwarf coconut palm was already on my wish list before I ever considered using the coir!

I agree with you 100% about not sterilizing the soil for seed starting.  I've never done that and don't plan on it.  If anything, I might myco-remediate soil that got contaminated somehow (like from my  neighbor's conventional crop spraying!)

I would also love to figure out a seed raising mix that doesn't require bought inputs. I have had moderate success with roughly half finished compost and half leaf mold. The leaf mold helps add some fluffiness to the mixture. It still doesn't behave quite the way I'd like. Might actually be too much leaf mold? The moisture retention isn't quite what I'd hope. I need to experiment more with making very small batches (like a pot-worth) then watering the mix to see how it behaves, and continue experimenting til I find a happy medium.

Heather, if you can find the leaf mold made by mother nature that would probably be a perfect material for seed raising unless it might be too rich.

I am fortunate to have lots of oak trees on my 40 acres.

At the base of these trees out to the drip line and years and years on leaves just waiting to be made by mother nature into leaf mold.  Only shady clusters work though.

Sunny trees have grass that grows making it hard to push back the leaves and find the black gold.


The National Forest frowns on the harvesting of certain items though I wonder if asking for one trash bag full wouldn't hurt.

Dr. Redhawk,  Can this potting mix also be used in a sand bed covered with shade cloth and used to grow out cuttings?

Thank you.