I got a catalog from Johnny's seeds the other day and saw their soil block makers. I've been looking into them and I'm thinking about trying them to start my garden plants this year as an experiment. I'll make my own soil block maker to test and may buy the nicer ones if I continue using them. I do have a few questions about their use I was hoping you could help me answer.
One question is about the compacted soil. It's my understanding that with plants, especially young seedlings, you want to make the soil light and airy to allow it to spread it's roots easily. However, if you're compacting the soil enough to hold a block shape, does this not prevent easy spreading of the roots.
Another is about potting up. I've seen with ones from Johnny's Seeds, that they make an indentation the correct size to drop a 3/4" cube into the top of a 2" cube. Would it be preferable to just start the seed in the bigger cube if you knew it was going to need the extra room before transplant or would you start it in the smaller cube and transfer it up. Maybe you just put it in the bigger cube if you needed more time than you thought.
What signs are you looking for to indicate that it's time to pot up?
How durable are these? I know you water them with a wicking action, but how long do they last? It seems to me that they'd tend to want to come apart. Are they just meant for the short time period (~2months max) that you'd start a garden plant before transplanting it into the ground?
Lastly, for this Q&A, has anyone used these for cuttings with success. It seems like they might be good for that purpose. Thanks for the help.
Here are some links and pictures of the soil block makers for sale at Johnny's Seeds at Sue's request.