On 11/08/2012 00:12, David Hare-Scott wrote:
Jeff Layman wrote:
On 10/08/2012 00:27, David Hare-Scott wrote:
Kay Lancaster wrote:
Treat clay soils with respect... they're difficult to grow on.

yes indeed.

D

A commonly held and vastly mistaken view, IMHO. Difficult to work
maybe. But they are not difficult to grow on at all, if you keep to a
couple of simple rules. Firstly, never try to plant anything when
they are soaking wet. Secondly, never try to plant anything when
they are bone dry. Clay is far more suited to growing many plants
than sandy soil; even those naturally found in sandy environments
will often more than just tolerate clay. I have grown heathers
without problem, and grown and fruited blueberries on clay (pH 6 -
6.5). I have even been able to move plants which are said to really
dislike being moved because a great lump of clay sticks to the roots,
and, to all intents and purposes, the roots really haven't been
disturbed at all. Try that with sandy or even "highly desirable"
loamy soil. The one plant I have given up with on clay soil is
grass. Where it is constantly wet, a lawn simply ends up a mess,
often with more moss than grass. The previous owner of the house I
moved in to had so much trouble he installed land drains, but even
those couldn't make a meaningful difference and in the end I had the
lawn removed (no great loss as I can't stand lawns anyway).
I live in the Sussex weald, and have been gardening on clay for over
25 years. And, believe me, Sussex clay is real clay. I have about 10
inches of claggy "soil" over a solid clay subsoil (solid with
ironstone lumps, that is. Even a pickaxe fails to penetrate some
parts. and I have to resort to a hammer drill if I want a deep hole).
The most difficult thing about gardening on clay is digging the damn
stuff; it is /very/ hard work. It even sticks to stainless steel
spades with a vengeance. And when dry, don't even bother with a
hammer drill - it's not worth the effort. Wait until it's workable
again.
But when it grows stuff, it is brilliant. It holds moisture; it holds
nutrients; it anchors. It tends to help withstand frosts much better
than lighter soils.

My situation is similar to yours, a layer of topsoil over plastic clay,
though I suspect my topsoil is naturally better. I agree that clay soil
holds water and nutrients well and can produce great crops. Every time the
region goes into drought I thank my stars for the clay underneath that acts
like a big sponge and keeps my pasture growing for months without rain.
Having had very sandy soil (that I was always trying to build up) and very
clayey soil that I have to break down I will take the clay.

BUT You have to have (or to make) actual soil. Clay by itself ( I mean the
plastic stuff you can mould into complex shapes) is hopeless. The process
of amending it takes years of effort and some skill. The choice of plants
has to be considered carefully as many will die in a wet spell due to lack
of drainage and it is impractical (for me anyway) to landscape the whole
garden for drainage and to amend all its soil to prevent the problem. As it
is all my fruit trees grow in mounds and my vege garden has raised beds with
drain paths running down-slope: at considerable effort and cost.

Clay is not for people who just want to plop something in the ground and see
it grow. I thought it interesting that in response to "Treat clay soils
with respect... they're difficult to grow on." you first deny that it is so
and then go on to explain all the difficulties that have. :-)

Did I? Read my post again.

You are confusing "growing" with the act of digging or cultivating. For
the latter, good loam or even sandy soil wins every time, as the job is
easy. But once in, plants grow much better in clay without a lot of
additional help such as watering and use of fertilisers.

--

Jeff