The vineyard floor consists of the area that is on the ground directly under the main arm of the vine and has a width of about 24 inches. Muscadines have shallow roots that are typically 8-12 inches below ground level and run parallel to the top wire about 5 feet on either side of the trunk. The ideal vineyard floor would be absent of grass and weeds in order to eliminate the competition for soil moisture and nutrients. If every drop of moisture and every ounce of fertilizer goes straight to the plant it will lead to a happier and healthier vine.

Ways to maintain the vineyard floor

1. The most common approach is the use of herbicides such as round-up or paraquat. Herbicides are absorbed through tender vegetation or leaves on plants. If you have new plants in the ground less than a year we recommend using either jumpstarts or blue x plants shelters for herbicide protection. On new plants there is a lot of leaves and tender growth low to the ground and the use of plant shelters will protect the young growth from unwanted spray contact or spray drift.

If the vines are 2 years and older usually the trunk area has a mature bark absent of tender vegetation and you can safely spray herbicides across the bark of the trunk with no threat of harming the vine.

Common herbicides used in the vineyard

A. Round-up is a systemic product which is absorbed into the root system and will usually kill any unwanted grass or weeds.

An average growing season will usually involve 4 round up applications for control of the vineyard floor. Once in early spring, once in late spring, once mid summer, and the last spray late summer or early fall. If we have a wet growing season an additional application may be needed

B. Paraquat – this is a restricted use herbicide that is a contact herbicide, it will burn down any growth it comes in contact with but is not absorbed into the root system. We will usually make one paraquat application early summer for control of morning glory’s, round up is not effective on contol of morning glory’s.

C. Poast – herbicide that will give marginal control of grasses and can come in contact with tender vegetaion on the muscadine vine with no negative impact. Ideally this product is applied when grassed are 2-4 inches tall and multiple applications are needed for control.

***   Make sure to NEVER use 2-4-D ***

Always read labeling to make sure grapes are listed as a crop the herbicide can be used on

2. Landscape fabric or weed barrier. This product is a woven fabric that can be laid down on the ground to prevent grass and weed competition. I would recommend using this product if you did not want to use herbicides and would place a 24 inch wide strip under the row covering 5 feet on either side of the trunk. Landscape fabric or weed barrier will allow moisture and fertilizers to pass through the fabric while preventing grass and weed competition. You may mulch on top of the fabric with either pine straw or other aged pine bark materials.

Other thoughts to consider.

If you are weed eating or cutting the grass under the row you are not eliminating the grass and weeds and the vine is still having to compete for water and nutrients.

If you are bringing in a 6-8 inch layer of mulch under the main arm you can promote surface roots. The muscadine roots will actually want to grow up out of the ground and into the mulch layer and if we have hard winter temperatures or hard freezes you can get root damage.

Let’s Grow Together
Greg Ison
isons.com