Success with Grapes

My father is passionate about his grapevine. He prunes the vine in winter when there are no leaves, and again in summer when it is covered in leaves. When the fruit sets he drags out the mesh and clips it neatly over the vine to keep away the birds. After that, he can often be found peering under the netting checking for fruit. He doesn`t want to miss a single bunch. On the other hand, my mum is always asking me to tell Dad to back off with the secateurs in the summer; she`s convinced that Dad takes far too much off and could be damaging the vine. With this in mind, we`ve put together some notes to help make your grapevine growing experience an informed one...

Position and Soil Types

The best position for grapevines is where they receive full sun with good air circulation. They will need some protection against strong winds. Train them over trellis, pergolas or around a patio or veranda.

Grapevines require a good deep soil that drains well. Adding sand or small stones to the soil will help improve drainage in heavy soils. A pH in the range of 5.5 - 7.0 is ideal. If you are unsure of the pH of your soil, pH soil tester kits are available in at your local store.

Planting

Plant out after the risk of frost is over. If the vine is dormant, cut back to 2 or 3 buds. Dig a hole slightly larger than the container that the grape is in at present. Add compost and a slow release fertiliser such as Magamp. Sprinkle the fertiliser around the edge of the hole to make the roots stretch for it. Water thoroughly. Plant vines 1.5 - 3 metres apart, depending on the vigour of the variety. Protect with a slug and snail repellent at the onset of leaf growth.

Watering

Ensure the vine receives consistent watering, particularly over late spring/summer when the fruit is setting. You may need to give a good deep watering just prior to bud burst if the winter has been dry.

Mulching

Mulching with materials such as compost will help prevent moisture loss and prevent weed growth. Remember to keep the mulch clear of the trunk.

Feeding

Feed with a fertiliser such as General Garden Fertiliser in early spring and once again in the growing season whilst the vines are young. Keep the fertiliser away from the trunk and water in well.

Pruning

The vines need to be pruned each winter when dormant. There are two forms of pruning to achieve the maximum amount of fruit:

Spur Pruning

This system is excellent for training vines over fences and pergolas. The trunk is trained to the required height and two lateral arms are maintained. All the canes arising from these two main arms are pruned back leaving 2 or 3 buds at the base at intervals of 15-20cm apart along the main arms. All other canes should be pruned out, as well as any shoots which arise from the main trunk. Each of the 2-3 buds produces canes in spring then produce fruit in summer-autumn. The following winter cut off the upper 1 or 2 canes and prune the lowest one back to 2-3 buds. This lower one is the spur which gives rise to the next season`s canes and fruit.

Cane Pruning

A trunk is trained to the required height and two lateral arms developed. All the canes that develop from these two main arms are pruned back to 8-12 buds in winter, and the main arms are kept short. Select only 3 or 4 strong canes on each arm, and wrap these around the wire/trellis or tie them to the fence. Select another 3 or 4 canes to be shortened back to 2 buds only. Remove all other canes. The 3-4 canes that have been wrapped around the support will provide the fruit canes for this year, whilst the shortened canes provide the fruit the following year.

Maintenance

The most important maintenance aspects for grape vines are:

	Keeping weeds free to prevent competition and increase airflow and reduce disease.
	Foliage trimming (not pruning!) during the summer to allow better light to buds and help ripening.
	Before fruit sets, cover with bird netting to prevent fruit loss.

Harvest

Grapes ripen from late February onwards. Hot, dry weather helps them to sweeten, whereas rain can set them back. Bunches are best cut off with secateurs.

Protecting Vines

Sadly, in this case, this includes birds. So often we are trying everything to encourage them into our garden - but they need `training` to keep away from fruiting trees and vines. The only way to do this is to cover the vines with a mesh which is fine enough to stop the birds from getting through the gaps. As far as other pests and diseases, prevention is the best way to approach these things. A preventative spray programme is shown below.

You may sometimes see grapevines under what appears to be white blankets during the months of late winter / early spring. Well you wouldn`t be far wrong. Frost cloth, normally a white, mesh cloth is often used to prevent damage to new growth on the vines by commercial growers. This mesh is available through your local store and is laid across the tops of the vines before the first frost occurs, and is removed when the danger has passed.