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Grape Grower's Notebook
March 9, 2000 |
Organic Vineyard Floor Management As this picture illustrates, a vineyard site as flat as a billiard table is ideal, but not essential, for clear cultivation.
In the page on "Organic Vineyard Site Selection", we suggest one of the goals of the organic grower should be clear cultivation of the vineyard floor. Where clear cultivation is
not practicable (due to the threat of erosion) we suggest the alternative of aisles planted with grass and clear cultivation under the trellis wires only. If you choose not to use synthetic and systemic pesticides
then you should go the extra distance to try to keep the vineyard as clean as possible. Weeds serve as as an excellent host for fungal disease, and their control by all grape growers
should be a part of routine. For the organic grower, weed control can make the difference between success or failure. Vineyards differ from orchards because the foliage and fruit
are typically much closer to the ground. Mildew spores are easily splashed back onto vines from weed hosts. Perennial weeds are definitely the enemy, but annuals, such as Mare's
Tail can grow among the vines and grapes to a height of six feet in one season, and serve the same host function as the other weeds. Where Black Rot is a problem (see page in "Grapevine
Maladies and Pests"), and unless you are willing to use one of the "almost organic" pesticides recommended in this section of the GGN, it may serve as your Achilles heel. Eliminating
weeds and other vineyard sanitation methods will definitely help to reduce the threat of Black Rot Options Assuming a planted, three year old vineyard, floor
management routine by the organic grower might be based upon the following options.
- Clear Cultivation through use of a landscape (or lighter) three-point hitch rake for cultivation of the aisles, combined with:
- Mechanical weed control under the trellis wire (hoe, tractor mounted grape hoe, or various power cultivating devises run by tractor power) or,
- Spot killing of weeds under the wire with propane torch cauterization, detergent based broad leaf herbicides or other herbicides acceptable to the grower.
- Aisles planted to grass using the same options under the wire and spot killing weeds in the grass with detergent based, or other acceptable herbicide.
In a vineyard less than 3 years old, weed control is still necessary, but grow tube protection is recommended for the young vines. Young vineyards should not serve as an
on-the-job-training site for operation of mechanical weed control devises under the trellis wire.
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