Roses as an early warning systems for vines

Roses apparently are a superb early warning system for vines; Driving through the Corbieres you occasionally see roses planted at the end of rows of vines. Often the same vines that you see sheep grazing in Winter. This is not because the vigneron has a poetic streak, it is because roses are an early warning system for two types of treatable but dangerous funguses that attack vines. Both roses and vines have very similar soil and water requirements and both are vulnerable to mildew. However roses usually fall victim to mildew before the vines get seriously infected.

Mildew is the bane of the vigneron’s life. A serious infection in the vines has only one solution; pull them all up and start again.

There are two forms of mildew that attacks roses and vines.

Powdery Mildew- A white powdery fungal infection that attacks the green parts of the vines, if it reaches the grapes they will split and rot. There is no cure but if caught early a sulphur spray will prevent the fungus from attacking the vines. Sulphur sprays are allowed in organic agriculture because it is a mineral not a complex chemical; and therefore natural not synthetic.

Downey Mildew- This fungal infection first attacks the underside of vine leaves leaving yellow spots. If untreated it causes the leaves of the vines to fall off, basically stopping the plant from gaining energy from the sun. If the roses start suffering then a treatment of Bordeaux mixture, a mixture of copper(II) sulphate (CuSO₄) and slaked lime (Ca(OH)₂) . This mixture prevents the fungus from reproducing thus stopping it dead. This is also allowed in organic agriculture although there has been some concern about the build up of copper in soil and it’s effects on soil life.

According to GardenKnowhow.com The following pants are good companion plants for grape vines.

Hyssop Oregano Basil Beans Blackberries Clover Geraniums Peas

“In the case of hyssop, bees love the flowers while the rest of the plant deters pests and improves the grape’s flavor. Geraniums also repel pests, such as leafhoppers. Blackberries provide shelter for beneficial parasitic wasps, which also kill leafhopper eggs”

Personally I am not convinced by basil,  basil is great for keeping predatory insects off tomatoes however it needs to be planted at the foot of the tomatoes to work, I am not sure vines would appreciate the water levels basil needs.

For information on the Domaine de Montrouch’s selection of old Roses see here.