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Setting Up the Vegetable Plot

by John Harrison on Sunday, 27th March 2011

I'm a bit worried about getting the vegetable plot sorted. Digging holes for the trees in various spots has given me a good feeling for the soil. On the surface, it's a thick grass and moss layer. So thick that getting the spade in is hard. Below that, we have about 4" to 6" of matted roots and then we're in to mixed soil and stones. A lot of stones. The soil changes to sub-soil about ten inches down.

It's not a heavy soil of itself, more towards the sandy than clay. But all those stones and the shallow depth to them means some root crops like tubular carrots, parsnips etc are not going to be possible in the ground.

I know it's going to be acid to say the least, my neighbour said he'd tested his and its pH was just 4.6. That's terrible but not a major problem as adding lime will sort it out. I'll bet pounds to pennies that it is also nutrient poor. When I test it, I'll know for certain just how bad. Once again, not the end of the earth. Adding fertiliser will cure that.

The big worry is the shallow depth and lack of humus. That's not so easy to cure. All vegetables like a good depth of soil and humus (organic matter) is critical to success. On my Wistaston allotments it took years to increase the depth of the soil. Double digging, even bastard trenching to gradually turn the heavy sub-surface clay to fertile top soil. Continually adding large quantities of compost and manure as I went.

We had mountains of used turkey litter, hills of horse and cow manure and skip loads of municipal compost added to the soil. I actually lifted the height of the plot by over a foot over the years. Nothing compared to the market gardeners of Paris in the 1800s who were said to have lifted their plots by 2 metres (6 feet) with the additional humus.

I can't say this strongly enough, plants grow in soil and the secret to success is a good depth of humus rich fertile soil. Achieving that is a task that takes years, not a garden makeover.

Clearing an overgrown allotment plot is hard work, but the soil has been productive in the past. Here the land has only been used for grazing sheep and nothing has been done with it for many years. It's actually a much harder job.

I must make it clear, I'm in uncharted waters here. At this point I don't know what I'm going to do for the best. Making compost and sourcing manure is a given as is adding lime and fertiliser, but obtaining the depth of soil and quality of soil is the problem.

My first thought was to strip the turf off, stack it up to rot down and dig over the ground. However, just stripping off the turf is one heck of a job as it's so tough. Even if I did that, there's little usable soil below it.

The second option is to spray the plot area with glyphosate to kill off the grass and then either dig it over or borrow my neighbour's tractor and plough it. This should provide a thin base to grow on at least.

What I may do is to go for raised beds and grow in those, although that still leaves the problem of building up the depth of soil in them. I could buy in topsoil, which is expensive, or look around for a bulk compost supplier (I mean lorry loads, not bags) and take it from there.

I've never been a big fan of raised beds, but this might be my best route. Apart from anything else we get high rainfall and the vegetable plot will be on a sloping hillside. Rain falling higher up the hill will tend to wash the soil downhill without the stabilising effect of the turf. Level raised beds will keep the soil from being swept away.

Apart from wooden sided raised beds, I've a couple of kit beds I brought with us. A metal bed kit from Everedge and a Linkabord raised bed kit. Since they'll be fairly quick and easy to set up, I'll do those asap.

I know we'll get there in the end, it's just which is the best road to take that's the problem.

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