Use of Soil Blocks for propagation

[RhysParticipant]

Peter – certainly a fine advert for using soil blocks for lettuce – I may well emulate you for my second pick-and-come-again sowings which will be done at the May full moon. The first set are doing fine after being picked out of modules, but they were rather smaller at transplantation than yours are.

My blocker is a 1.5 inch block size, so I guess my plants are smaller at transplant than yours. Perhaps I will acquire a 2 inch one as well next year…….

[RhysParticipant]

Peter

Out of interest, I transplanted my sweetcorn plants grown in soil blocks yesterday (put them under fleece too!) and I noticed that, far from the roots stopping growing at the soil block edges, they grew into neighbouring blocks, with the result that you have to be careful lifting them not to tear neighbouring blocks. It’s not a major problem, but if you want the roots to stop at an air barrier, I guess you need to keep soil blocks with a clear space between them and their neighbours, something I neglected to do this time.

I suspect I should have planted them out sooner, but as with any new technique and new seed supplier, you err on the side of caution (I left 4 weeks prior to transplantation – next year I will see if a timetable can be used to allow transplantation two weeks after sowing).

The scallions were transplanted out in blocks 3 weeks after sowing and have taken OK in the garden.

[Peter MaughanParticipant]

Rhys
I agree. There comes a time when the seedling outgrows the soil block, depending on the size of the block and the vigour of the plant. For example, the lettuce seedlings that I was proud to show earlier eventually started to show signs of distress because I didn’t get them planted out soon enough.
For tomatoes, I’ve moved 2 inch blocked seedlings on into 4 inch blocks and the plants are growing strongly.
As an experiment, I’ve sown peas directly into 4 inch blocks, 5 to block; the greater depth of soil in a 4 inch block should give the strong roots of peas plenty of space to grow.
As an allotment holder with a plot on a steep slop, at the top of a narrow path, I cannot deliver the large quantities of compost/manure that Charles uses but I’m hoping that planting out seedlings grown in 4 inch blocks will be equally successful, even if labour intensive.

[RhysParticipant]

Peter – interesting rationale for you using soil blocks! An ingenious approach.

Have you thought about making terraces across the slope and then constructing Hugelkultur beds to provide in situ slow-release compost within your no-dig beds?

You might only make one a year, as clearly you’d only be able to bring in the twigs and branches in small amounts given the nature of your plot. But each one is supposed to last for 10 – 20 years.

I agree with you on the effort required to produce enough compost – even for 50 square metres, I find I need two wire cages of just under a cubic metre volume each, allied to four green compost bins filled sequentially to produce enough. In addition, I do an annual run to the horse stables to build a big pile of manure which rots down over 12 months and then has a winter spread over the bed for potatoes. And then I use grass cuttings and comfrey leaves to hill up potatoes which produces a good quality soil the season after (I mix that with moss peat, horse manure or whatever I have available).

Even at 4cm annual coverage, I need 2 cubic metres of compost or manure to cover all my beds. I”ve just about got there, but it requires a ‘production schedule’ to create it all!

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