On Fri, 3 Jan 2003 11:20:04 -0000, "cjw.1"
wrote:

"Rodger Whitlock" wrote in
message ...
It would help to have somewhat more information: Is that layer of
clay natural, or is it excavated soil that's been dumped on the
site?

What's under the clay?

Rodger, Under the clay is gravel. The clay is natural, a neighbour tells me
that the surrounding area used to be famous for brick making.

This triggers a series of thoughts:

1. Gravel under the clay: this means that if you put in land
drains, you can dig a sump into the gravel layer at the low point
and lead the water into it; the gravel will probably take the
water away quite nicely.

2. Good sticky brick clay is an excellent starting point for a
very good garden. It holds both moisture and nutrients.

3. Digging will be a problem: You are likely to find that your
clay is stickily unworkable in wet weather, and too bricklike in
dry weather.

4. Clay puts a real strain on garden tools. Don't waste your
money on cheap, poorly made digging forks in particular. Look for
very strong one. And when you dig, take *little* fork- and
shovel-fulls.

5. Scout out local sources of cheap organic matter in bulk.
Manure, fallen leaves, nearly anything will do. In my experience,
putting on fairly thick mulches of organic matter greatly
improves a clay soil, both by adding humus as it decomposes and
by providing food for worms and other soil denizens. Finished
compost is not as good as fairly rough, partially decomposed
material. Note that I say "mulch" -- you don't have to dig this
stuff in.

6. Adding sand is a waste of money and time.

7. If you are in an acid-soil area, adding lime will flocculate
the clay and make it easier to work.

8. Green manures will also help.

9. Regular *light* fertilization will bring up the fertility of
the soil and encourage plant growth. Plant growth cannot help but
have a beneficial effect; roots are *very* penetrating, and roots
of non-woody material are not fully perennial.

10. Some plants do not like clay soils and will not do well. I
have badly drained clay here, and I find that crocuses do not
thrive, though perhaps that has more to do with winter
waterlogging than the texture of the soil.


--
Rodger Whitlock
Victoria, British Columbia, Canada