Many years ago, around 8th grade maybe, I volunteered at a traveling daycamp as a Cadette Girl Scout. One of the camp projects was something like this:
So, I've thought for years that egg shells would be great for starting seeds. As a "square foot gardener" I also wanted to try growing seeds in vermiculite.
Here's how I have started my plants for now:
First, rather than buying those special seed starting mini greenhouses, I used the plastic clam shells that baked goods come in from the grocery store. I filled them with vermiculite and spread seeds around. Then I watered and closed the clam shell, gave it a week or two, depending on the seeds and:
The nice thing about these clam shells is that you can divide them with paper, and draw a line over the top of the whole thing with magic marker, and label the sections
While those were growing, I prepared my "planters." This winter I saved a few dozen egg shells. I prepared them by poking holes in the bottoms with a pin:
I did this to a lot of them:
Then I filled them with potting soil and transplanted the seedlings from the vermiculite to the egg shells:
Now, to put them in the ground, I'll just squeeze the shell and put in a hole.
In the picture above, you'll see that some of the eggs are topped off with vermiculite. The eggs are growing tomatoes and I want good roots. Knowing that tomato plants put out roots from the stem if buried, I covered them up as high as I could with vermiculite, and am seeing if it makes a difference in plant growth.
Another thing you can see above is that in the back, there's a cardboard egg carton with more seedlings, but not in shells. This is another experiment, also doing the vermiculite top-off experiment.
Before some science teacher comments that there are too many variables to call it an experiment, well, I know. There's no true control group. Luckily, this isn't a science project, it's a kitchen project for my garden, so I'm ok with it not being done "correctly."
The tomato varieties are Bloody Butcher, Yellow Pear, and some sort of hybrid cherry tomato that's supposed to grow so many it looks like bunches of grapes.