Agriculture Reference
In-Depth Information
WEEDING AND COVER CROPS
Weeds in the vineyard are one of the biggest challenges for the organic grower. They
use up sunlight, nutrients, and water that you would prefer to have going to your grapev-
ines. Weed competition in the first year can reduce vine growth by as much as 50 percent;
in worst cases, they can choke your vines. Weeds are hosts for pests and for fungal dis-
eases. Those with large, succulent roots can attract gophers.
If you have prepared your site well, you will hopefully have cleared the worst of the
perennial weeds. But you will never be free of annual weeds and so controlling them is an
ongoing maintenance task in the vineyard. Cover crops planted in the middle of the rows
and physical removal of weeds at the base of vines under the trellis are the basis of your
weed management program.
At the base of the vines, keep the weeds down by clearing weeds with a string trimmer,
shovel, hoe, mulch, or an organic weed control spray. I have used a spray with 25 percent
vinegar with some success. Other organic contact herbicides may be soap-based or contain
some other material, such as clove or citrus oil. Be careful not to spray any herbicide on
the developing vine; in the first year, your grow tubes will protect the young vines but after
that you may have to use primarily mechanical means of weed control close to the trunk.
If you do have grow tubes in place, you may need to lift the tubes to clear out any weeds
growing up inside them.
Some growers use a thick mulch around the vines and under the wires to help keep
down weeds. This can work well in a small vineyard, but you will have to replenish the
mulch every one to three years. Other growers use a small propane flame thrower to con-
trol weeds. I prefer not to use these devices as I am concerned about hurting my vines and
potentially causing a fire.
Between rows, mowing and cover crops are the best methods of weed control. Mow-
ing provides mulch—as long as you leave the clippings on the ground—and a natural
source of nutrients. You can also use a small riding mower or even a handheld string trim-
mer to break up any larger prunings on the ground.
