Hi! Peter, If the cover crop is slowing vine growth, it suggests that there is a Nitrogen shortage. The cut cover crop and any mulch is mostly carbon and needs a specific proportion of nitrogen to break it down. It is important to start with a legume with the right inoculant to help set nitrogen from the air, into the soil, in a form the plant can use. The break down of carbon, also uses large amounts of nitrogen, which may be what has happened. When you get a "nitrogen credit" in the soil, it is OK to have a non nitrogen fixing cover crop.
The use of the Preps will help the whole process. I also use the combined compost Preps, sprayed onto the freshly slashed cover crop, which seems to help it break down. If you have the time and a good Whipper Snipper, using the line, not blade, you can make a little guard on a long handle, which you can put against the butt of the vine and slash right to the butt, at ground level. I do not see properly managed cover crops as competing. They will keep out weeds and should produce all the N and C your crop requires. While they will use some water, if slashed fairly often, they also reduce water loss from bare soil and the effect of heat on the root run. In Oz with our mainly shallow soils, it is important to use all of it we can. A sun dried inch or two is wasted country and it also kills feeder roots. Gil J Peter Young wrote: > Gil, We had a marvelous green manure crop this spring which, when we > couldn't get control of it in the vine row, completely shut down vine > growth in early summer. It is a young vineyard and apparently very > sensitive to competition. Once the green manure crop finally fell away > natually, the more noxious north coast weeds began to appear because > of our irrigation. In some areas we did sow a clover vine row cover > crop, but it was just a competitive. It's sad that next door, my > conventional farming neighbor who uses a pre-emergent over the winter > and then regularly applied RoundUp through teh growing season had much > better growth and vigor with less water and a lot less fertilizer. We > had hoped to only try to keep the 18" around each vine clear, but that > is turning out to be impractical and next season we are going for an > 18" to 24" wide strip. The aisles will continue to have cover crop in > them providing habitat. Our biggest concern this year is getting in to > the vineyard at the right points in time over the winer to use the > vinegar and the number of passes we'll have to make each season since > vinegar has not effect on the roots. Peter
