Happy little three-week-old tomato starts,
growing away in their soil blocks.
It's been a month now since starting seeds in the soil blocks. First with the brassica crops and then with the tomatoes, peppers, tomatillos and eggplants that followed a few weeks later.
So, I have to say that they work pretty well with a few minor flaws that required a bit of special treatment. First and foremost, DON"T LET THE BLOCKS DRY OUT. Otherwise you will end up with, not blocks, but dry little "bricks" of soil that water will run right off of. Also, and related to the above, don't pack your blocks too tight. Next time I think I will block the soil a little less firm. The advantages of this (I hope) will be that they not only will accept water more readily but also be easier for seeds to germinate and push up through. In addition, next time I will also screen out the larger pieces of pumice in the soil mix. Any piece of pumice, say, over 1/8" will create a major barrier, especially for small seeds, that will be very difficult for a seed to push around as they germinate.
Things I have so far appreciated about soil block, aside from not having to use pots or coco pellets, is that the soil mix actually has some nutrition for the seedlings. "Coco peat" pellets, so far as I can tell, don't have much to offer in the way of fertilizer. Also, even though the blocks have a tendency to dry out, at least you can pick up one and see all the surfaces (not just the top) thus it's easier to determine if it really needs water or not. Last year, with the cow pot experiment, I would sometimes find the inside bone dry when I went to transplant.
Next year I might invest in a 4" blocker. Woo hoo!
Roots emerge. Almost ready for up-potting.