weird plastic sheeting

Hi,

a friend of mine moved into a new house and we
went to check out his garden. We found that large
sections of his garden beds had sheetings of black
plastic covered by a layer of mulch. Growing in
that were some not so healthy looking camelias.
I thought that was a really weird thing to do. The soil
underneath the plastic looked like dead dust with
no evidence of any bug life.
Why do people use those? It seems that the plastic
kills the soil off and it would also keep the water away
from the roots.
what's the purpose of them, just to keep weeds away?

barb.

"freebird" wrote in message
...
Hi,

a friend of mine moved into a new house and we
went to check out his garden. We found that large
sections of his garden beds had sheetings of black
plastic covered by a layer of mulch. Growing in
that were some not so healthy looking camelias.
I thought that was a really weird thing to do. The soil
underneath the plastic looked like dead dust with
no evidence of any bug life.
Why do people use those? It seems that the plastic
kills the soil off and it would also keep the water away
from the roots.
what's the purpose of them, just to keep weeds away?

barb.

It's really only there to keep weeds down.
As well as that it stops water getting to the roots, gets so hot in summer
that it can burn roots and totally destroy and good organisms in the soil
The only use it can have is on driveways that have gravel as the surface,
and the plastic provides a weed supresser and sub drainage as the water goes
down, hits the plastic then runs away if on a slope. Even then the weight of
the car and sharpness of gravel can puncture the plastic, allowing water in
and undermining the driveway in severe cases. Also weeds will still come up
in organic matter that builds up in the gravel.
Actually, the best use on the garden would be if you had a very weedy garden
bed with no plants that you wanted to plant out and kill the weeds and
seeds organically. Just put the plastic over the surface on a hot day, leave
for a week and it should kill the whole area. Still, it doesn't really help
the organisms in the topsoil.
Rip the plastic up in your friends garden, add some good organic matter or
topsoil, and mulch it and the plants may take off.
You may also find you need a wetting agent (wetta soil or similar) to get
the old soil to hold moisture, added to the good deep waterings.
Good luck

"freebird" wrote in message
...
Hi,

a friend of mine moved into a new house and we
went to check out his garden. We found that large
sections of his garden beds had sheetings of black
plastic covered by a layer of mulch. Growing in
that were some not so healthy looking camelias.
I thought that was a really weird thing to do. The soil
underneath the plastic looked like dead dust with
no evidence of any bug life.
Why do people use those? It seems that the plastic
kills the soil off and it would also keep the water away
from the roots.
what's the purpose of them, just to keep weeds away?

barb.

It's really only there to keep weeds down.
As well as that it stops water getting to the roots, gets so hot in summer
that it can burn roots and totally destroy and good organisms in the soil
The only use it can have is on driveways that have gravel as the surface,
and the plastic provides a weed supresser and sub drainage as the water goes
down, hits the plastic then runs away if on a slope. Even then the weight of
the car and sharpness of gravel can puncture the plastic, allowing water in
and undermining the driveway in severe cases. Also weeds will still come up
in organic matter that builds up in the gravel.
Actually, the best use on the garden would be if you had a very weedy garden
bed with no plants that you wanted to plant out and kill the weeds and
seeds organically. Just put the plastic over the surface on a hot day, leave
for a week and it should kill the whole area. Still, it doesn't really help
the organisms in the topsoil.
Rip the plastic up in your friends garden, add some good organic matter or
topsoil, and mulch it and the plants may take off.
You may also find you need a wetting agent (wetta soil or similar) to get
the old soil to hold moisture, added to the good deep waterings.
Good luck

G'day freebird,
Black plastic was all the rage back in the 60's and 70's
as a weed treatment in the days before glyphosate. It was a bit of a
landscaping fad like cocos palms. As you noticed, it destroys soil ecology
and should be lifted. However don't be surprised to find the garden has
large infestations of oxalis or onion weed that will keep you busy for a
while. Allow some time for problem weeds to show themselves before new
planting's, and this will also allow the soil to become reactivated into a
healthy growing medium. Also be a bit careful when lifting the plastic, as
on the several times I have performed this service, I often found colonies
of funnel webs underneath.

China
Wingham
NSW