Non-chemical solutions for growing grapes
There will always be some controversy about organic growers who rely on chemicals to get started, although this is by far the norm in viticulture. The issue is only important for young vines, as established vines can tolerate more competition, and there is a variety of tools and equipment, such as under-vine weeding knives and slashers that will swing under the canopy. Other solutions are mulching with organic matter, flame and plant competitions (such as clovers and medics). These methods are all problematic for young vines though, as they can easily get burnt or smothered.
The best solution for non-chemical establishment is to use a weed mat of some type. There are individual stem products, such as squares or disks of hemp fibre, jute, wool or cardboard, but the purchase price of these products and time taken to lay them is high.
One of the better examples of non-chemical establishment is from the small vineyard of Ian Cairns, at Liffy in Tasmania. He uses woven plastic weed mat (organic growers should not use non-woven plastic mulch) with dolomite around the slot cut for the individual vines. While establishment cost for this is higher than herbicide use, the mulch will last for at least three or four years and possible much longer if treated with care.
The best form of weed control is to have a healthy, established cover crop to smother weeds. Straw (or compost) mulching is used at Penfolds organic vineyard (Clare, SA) and others, but it does have a high 
establishment cost.
Careful mechanical control of weeds/cover crops using discs is acceptable if based on strategic timing to reduce negative effects, such as pulverised soil, erosion and compaction. Under vine weeds are controlled by brush cutting, hand hoeing or cultivation use of a Clemens under-vine weeder or similar tool.
The Clemens weeder is highly regarded as an effective under vine treatment where mulching is not effective or where frost control is critical. Hand hoeing remains a useful strategy and if outbreaks of problematic weeds are controlled while they are small in extent they can prevent significant work later.
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