On 6/29/2009 9:24 AM, jeff wrote:
David E. Ross wrote:
On 6/27/2009 3:54 PM, mphowells wrote:
Hi I live on a slope and after my two patio slab depth patio area my
garden slopes down from the right to the left quite considerably. It
means there is not much garden for the children to play in.

I therefore want to level it out. Question is, do I:

1 - build up the left to bring the whole garden level and turn my 6ft
fence in to a 3 ft fence as a result.

2 - dig down the right to level it with the left and create a step down
from the patio to the garden. This keeps the 6ft fence and therefore the
privicy.

Not sure if it matters but eventually I'll be making the patio much
bigger.

Thanks

I would do both. Cut down on the right and use the "spoil" (the dirt
that is dug out) to fill in on the left. This means less cutting and
less filling. This is how tracts of homes are graded. There will be a
boundary separating the cut and fill; this is known as the daylight line.

That is exactly what I've been doing, didn't know the terms! I've
terraced my garden and a friends who has a much steeper slope.

A few hints.

Get a good mattock and loosen the soil with that, rather than a shovel.

You may find that when you dig down that the soil quality
deteriorates. You may wish to do some dirt sorting.

I'm going to reread David's post to pick up some new ideas!

Jeff


Sorting surface and subsurface soils might not be necessary. An old
gardening practice is to double- or triple-spit the soil. "Spitting" is
digging to a depth equal to the length of tines on a spading fork (which
is definitely NOT a pitch fork or hay fork) or the length of the blade
of a spade.

To improve the soil, you spit a trench, piling the soil on the side away
from where you plan to dig the next trench. Then, you spit the same
trench an addition depth, piling the soil next to the first pile. A
third spitting would be nice but not always necessary, depending on the
soil.

Next, you spit a new trench not only parallel to the first one but
actually in a way that merely widens the first one. The new trench is
one spit deep with the surface soil piled on the bottom of the first
trench. Then soil from the second spitting of the new trench goes into
the first trench on top of the soil from the first spitting of the new
trench. If you triple-spit, the bottom third from the new trench
becomes the top layer of the first trench.

Now you start another trench, filling in the second trench. Etc, etc,
etc. When you finally spit the last trench, the piled up soil from the
very first trench -- in the proper order -- fills it. Soil amendments
can be added while spitting. Phosphorus can be placed at the bottom
where roots will find it, but other nutrients should be withheld until
after plants are established.

This can indeed move the better soil down and inferior soil to the
surface. The better soil might even be beyond the reach of the roots of
annuals and some shallow-rooted perennials and shrubs. However, the
tilth is very much improved. If spitting is done correctly, it might
not have to be repeated for many years. (Of course, if shrubs are
planted, it will never be redone.)

Similar results today can be obtained with the use of a power
rototiller. You till a single width of the machine for the length of
the bed. You shovel the loose soil to one side. Till the same area
again and again shovel the loose soil beyond the first row that was
shoveled. Adjacent to the first area, till and use the result to fill
the first area; till again and complete the filling of the first area.
Etc, etc. Amendments can be applied before each tilling; the rototiller
will mix them into the soil quite well.

To level a gradual slope, use a rototiller to triple-spit the high side
and double-spit the rest. Just move some of the tilled soil from the
high side to the low. If the slope is more than merely gradual, a
grading permit might indeed be appropriate.

--
David E. Ross
Climate: California Mediterranean
Sunset Zone: 21 -- interior Santa Monica Mountains with some ocean
influence (USDA 10a, very close to Sunset Zone 19)
Gardening diary at http://www.rossde.com/garden/diary