Adventures in Soil Blocking

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I made close to fifty 1020 trays of soil blocks this year so I use a lot of promix.

They are very efficient for starting seeds. I just love my soil blockers.

 

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OK, I've just gotten a grand education on soil blocking, which I had previously looked at with skepticism. Thank you muchly for that! (scribbles 'soil blocker' on Christmas wish list)

I was skeptical initially as well, but I am so glad that I made the leap.

 

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Due to you, I bought a SS soil blocker. It worked great once I read the instructions. I didn't use it for everything, but I saw its value as the blocks stayed together for over two months!!

Rhodie Ranch, what size soil blocker did you buy-- and what kind of seeds did you start with it?

 

[Phaedra]

So far, I didn't go for the soil blockers because I already had a lot of good-quality module trays and pots.

However, I recognize the numerous benefits soil blockers offer. Module trays and nursery pots can accomplish similar tasks. In the past, once the roots of my seedlings had developed to a certain extent, but the outside was still too cold, I would push them up from the bottom of each cell and transfer them to a deeper tray containing some soil. This allowed their roots to grow freely. However, I haven't observed a significant air-pruning effect thus far.

This year, most of my seedlings, as well as young plants propagated from cuttings, bare-root perennials, and dahlia tubers, are occupying the spaces amidst the transplanted plants in the raised beds. Instead of becoming rootbound due to the restrictions of pots, these plants are now able to efficiently extend their roots and explore the underlying soil for essential nutrients and water.

Although these methods differ, they have proven useful for me in this context.

 

[Rhodie Ranch]

Ummm...its packed away now, but I think it was a 2" metal one with four squares at a time. I started eggplants, peppers, and dill in the blocks I made. I was able to use leftover containers from the grocery store (thanks Phaedra for that thread) to place them in.

 

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I am trying to germinate squash, cucumber, and melon seeds in soil blocks. Some cucumbers seem to do okay in a 1 1/2' block, however the squash and melons grow big quickly and do not seem well suited to even the 2" block. So I took a look around the house and located a small square pot that is made of flexible plastic; it's about 3" tall and 2 1/2" wide at the rim. The base is a little narrower than the top. This is sort of the ideal shape for a soil block, because once the dirt is packed in and the pot is inverted you get a base that is a tad broader than the top of the block-- which is perfect for the roots to spread out. I found a large red die on our game shelf to place in the bottom to form an indentation that could accommodate a large seed, and I held my finger on it while I filled in the soil around it so it didn't shift position. Once the soil was heaping over the top of the container I pressed down very firmly to compress it, and then I inverted it and squeezed gently to release the block. It worked pretty well, and my handy dandy tongs were able to gently grab the die and pull it out without damaging the block in the process. It will be interesting to see if the seedling can stay in a block this size for a week or so after germination.

 

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Most of the cucumbers in the large soil blocks sprouted a couple of days ago, and are now under lights to grow on. So far so good with the large blocks.

 

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Okra is thriving under lights in 1 1/2" blocks with new leaves filling in quickly; the various shades of green are so pretty! In fact these okra seedlings looked so vibrant, I just had to start a dozen more.

They do not recommend combining different varieties of seeds on one tray as the growth habits can vary a great deal; this mixed tray is a good example of a seedling mismatch. The little winter storage tomato seedlings are getting completely overshadowed by the dense canopy of okra leaves, so the tomatoes will get a bump to starter pots.

 

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Sometimes my seedlings of annual flowers outgrow their soil blocks, but are not yet ready to face the world. This was the case yesterday. I tucked a bunch of them into a wheel barrow full of compost so they can spread their roots for a couple of days while I am away. This will also buy me a bit of time so I can decide where to plant them.

 

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Learning about the Charentais melon 'Petit Gris de Rennes' in one of ninnymary's posts had me intrigued; I was able to order seeds, and sowed a dozen today. My June 10th experiment with large home made soil blocks has been very successful with cucumbers and watermelon, so I made more over sized blocks to accommodate the melon seeds. With the blocking mix that was leftover I made 1 1/2" blocks to start nasturtiums Tip Top Rose and Alaska Red Shades, as well as some pelleted flower seeds of Nemesia Seventh Heaven Bicolor Lavender.

Which reminded me that with soil blocking extra care needs to be taken when sowing pelleted seeds, and here's why. The blocking mix is very moist, and pelleted seeds more or less dissolve once they make contact with water. If you place a large number of pelleted seeds in soil blocks with the expectation that you can go back afterwards and firm them in for good contact with the soil you will be disappointed. This is because the pelleted coating turns to a wet paste almost immediately. I like to water the depressions in the top of the blocks first and then I firmly place one seed at a time, pressing down well once it is in place. After that I do not touch the pellets again, as they get all mushy and have a tendency to move around.