Agriculture Reference
In-Depth Information
The most expensive brands are not always the best: commercial organic com-
posts are highly variable, not only from brand to brand but also from batch to
batch - so when you buy, examine a single bag before you purchase the rest. If
it is sodden, full of lumps or contaminated with a suspicious-looking amount of
plastic (it seems curious that organic compost can contain such rubbish, but
there you are), look at a different brand. You can also buy compost in bulk from
the nearest supplier you can find (your local authority may be able to tell you
which they use), but unless you are lucky enough to live on a manufacturer's
doorstep-delivery costs are likely to be prohibitive, and the quality of bulk com-
posts can leave a lot to be desired. Always ask for a sample by mail.
Tip
Learn to hot compost
Hot composting is absolutely the best way to provide the large quantities of top-
quality organic compost that your tunnel needs, and is a skill really worth acquiring.
Any vacant area outside can be sown with a green manure such as rye, mustard or
forage peas specifically for the purpose of making compost - and all that goodness
can then be brought into the tunnel. Compost is black gold.
Leafmould
If you are working with very heavy or very light soils, the more organic material
you can add the better. However, there are limits to how much compost and
manure you can add before plants start to be damaged by the rocketing nutrient
levels, and this is where leafmould comes in. It contains very low levels of nutri-
ents, and so is a useful way to boost the level of humus in the soil without feeding
it. This humus acts as a reservoir for existing nutrients, which means that it helps
to unlock the plant foods in heavy soils, and can help light soils to hold on to
what they have.
Leafmould could not be easier to make. In autumn, collect the fallen leaves of
deciduous trees and pile them into an open-sided container such as a cylinder of
chicken wire nailed to a post, and leave it for a year or two. There is no need to
cover the cylinder unless the leaves tend to blow away.
Excess salt build-up
Any time you're adding chemical fertilisers to the soil, liquid or otherwise, there
is a possibility that far more of a particular component is being added than the
plants actually want, and this leads to a build-up of salts that may damage them.
In severe cases, the plants just die. However, before that you may see a white
