I have a big garden and a guy offered me a pound of vermicompost (free worm poop!) to start my spring seeds with this year. So, I set out two flats instead of one and documented the results of a flat with just plain organic seed-starting soil versus a flat with organic seed-starting soil plus vermicompost.
I’m sold. Shopping for worms now, looking at plans for bins. I always start my own seeds this year indoors beside a window and under flourescent lights and I hover like a proud momma bird with hatching eggs. I’m really impressed, and thanks for sharing!
I would definitely recommend raising your own worms. You can get a pound of red wrigglers for 15-20 bucks. (I’ve gotten them locally for $15; they’re a little more expensive if you use Amazon.) I’ve got a worm bin in my kitchen and the little f*ckers have been eating my kitchen garbage for 5 months now. And no, the worm bin doesn’t smell at all, as long as you don’t overfeed the worms. It’s lots of fun. Like having miniature livestock.
By the way, you can easily make a bin super-cheap just by going to Walmart and buying a plastic bin with a lot of surface area and not much depth (no more than 8 inches or so). Drill holes in the lid and you’re in business. The worms won’t crawl out the holes unless you mess up and the bin becomes too damp.
I don’t know of any hard evidence that adding compost of any type leads to significantly greater seed germination. And thickness of seed leaves should be dependent on stored food in the seed, not any amendment to the soil. I’d also be concerned that adding a non-sterile component (composted worm castings) to a seed mix could pose trouble with damping-off or other soil-borne disease.
If the OP did a double-blinded experiment, sowing seed in separate flats with amended and non-amended soil (but not knowing which was which) and someone else evaluated germination percentage and seedling health without knowing which flats were which, that’d be more impressive.
Actually, you should look at if there are differences in temperature or how much water the two mixes retain. At this point, I would guess that the differences that you are seeing are more related to temperature or hydration.
Is one flat shaded a bit longer or exposed to a draft keeping it cooler?
The vermiculite could be holding more water, so the seeds in that flat achieved hydration faster than in the other flat. All seeds need to reach a certain percentage of water before they begin germination. If it hold more water, it will be interesting to see if there are damping off problems later on.
Thanks for this! I’ll refer my husband to your post as he seems reluctant to let me start vermicomposting in the pantry. I think your photos will be the clincher, given his perennial difficulty starting seeds for his vegetable garden.
Well, both flats are sitting side-by-side in the yard and have not been moved since the start. I have tried to treat both flats the same. Whenever I watered one, I watered the other as close to the same as I could. I’m pretty sure the vermiculite is approximately equal since I used the same bag of Jiffy Organic seed-starter divided into two parts and just added the one pound of worm castings to one of the halves of the Jiffy mix.
Certainly it’s not a perfect experiment, but it is pretty clear that the vermicompost has given the seedlings a boost.
I assume the worm castings are decomposing, and that will raise the temp some. Stored nutrients can be credited with the first seed leaves, but after the first seed leaves emerge, roots quickly grow and spread to take up nutrients. Check out this image of sprouting beans.
The worm poop probably holds moisture better and it was pretty damp when I added it to the Jiffy mix. It was dense, like mud, and I had to spend some time blending it in. So, maybe that has made a difference.
I had done some vermiculture when I had a backyard garden. It was pretty effective for having fresh compost to add to the plant beds on a regular basis, but we accidentally introduced soldier fly larvae into our setup. This apparently wasn’t a problem but a bonus. Compost IME generally does help a lot because of the higher moisture and temperature combination. Regardless of whether it makes them grow faster/stronger, it’s better for the plants to have regular sources of nutrient replenishment in the soil.
