Pat Meadows wrote:


I'd like to kill the grass in our (future) raspberry place,
to make tilling easier.

We have both clear plastic and black plastic.

Which one do you think would do this better?

Thanks!

Pat

I am going to quote Glenna Rose's post from last April. It is the
first one that explained the whole process so that it made sense.
-------------------------------------------

De-Weeding with Plastic

Moisten area to be covered.

Cover with heavy clear plastic, I usually use 6-mil purchased at a
home
improvement store.

Fasten edges and wherever else necessary to the ground. This can be
done
with fabric staples or even rocks or scrap lumber, keeping in mind
that
wherever the sun does not reach (or the plastic blows up from the
ground),
the weeds/plants will not be killed. It must be fastened so wind and
breezes do not raise the plastic and circulate air; the plastic must
be
close to the ground to effectively hold in the heat.

Keep the plastic firmly in place for several weeks.

Explanation:

It is important to use clear plastic, NOT black plastic.

Clear plastic allows the light through to sprout the seeds in the
soil.
The plastic holds in the moisture which also encourages seed
sprouting.
(The plastic will actually "rain" on the ground with condensation from
soil moisture.)

The heat produced by the sunlight will be held in by the plastic
causing
the soil to superheat killing the plants. While the plants are killed
by
the superheating, the animal life is unharmed as the worms, etc. are
mobile and can move away from the hotter areas of soil just as they do
on
an extremely hot sunny day.

As the plant life sprouts and dies, the remaining seeds will continue
to
sprout and also die from the extreme heat. It is important to leave
the
plastic in place until all seeds have a chance to sprout; this will
take
several weeks and will be dependent on how much sunlight (hours per
day
and time of year) reaches the plants. On my very weedy lawn, I
started
mine in May and left the plastic on all summer; when I seeded the
lawn, I
had the most beautiful, totally weed-free lawn you can imagine! The
best
thing was that there were no chemicals involved so no little critters
were
killed or damaged.

It is important to not cultivate this ground after removing the
plastic as
this works for only the top couple of inches (how far depending on the
seeds in the ground and how much heat got how deep). If the ground is
cultivated (raking is okay), it will turn up seeds buried deeper in
the
ground and they will sprout. That would still not be as many as are
in
the top couple of inches, however, and the weed population would be
significantly reduced. Of course, either way, all of the existing
weeds,
etc. are killed and their roots don't regenerate.

You will have people tell you black plastic will work. This is not
true!
Black plastic retards the growth; as soon as there is light again,
plants
will grow. This method sprouts the seeds and kills the plants. (It is
basically like continuously pouring boiling water over them.)

To assure yourself which will work best, try a 6-foot square of each
of
clear and black. You'll see for yourself. :-)

Happy de-weeding.

Glenna
--
Susan N.

There are 10 types of people in the world. Those who understand binary and those who do not.