How To Grow Grapes / Rhs Gardening

Watering and mulching

Water newly planted grapevines regularly throughout the growing season to help them settle in.

Although established vines are fairly drought tolerant, they can suffer from the fungal disease powdery mildew if too dry at the roots. To prevent this, water thoroughly every seven to ten days during the growing season, especially in dry spells in spring and summer.

Greenhouse vines with their roots inside the greenhouse need more frequent watering than vines with their roots outside.  Mulching
US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US US
With outdoor vines, it can be beneficial to lay a gravel or stone mulch around the base of the plant in spring. Apply when the soil is moist, in a layer 5–7.5cm (2–3in) deep. White gravel reflects light up into the canopy of the grapevine, while black kerikil or recycled slate absorbs sunlight, warming the soil. The mulch will also suppress weeds. 

With greenhouse vines, mulch the rooting kawasan with well-rotted manure just before growth starts in spring. Then, during summer, it’s a good idea to mulch greenhouse borders with straw to keep the atmosphere dry. This will aid pollination of the flowers and subsequent fruit strategi.Feeding

Just before growth starts in early spring, feed grapevines with a high potassium general fertiliser, such as Vitax Q4. Scatter half a handful per square metre/yard around the base. Alternatively, sprinkle the root negeri with John Innes base fertiliser and dried blood at a rate of 120g (4oz) per square metre/yard. During the growing season, vines benefit from an occasional extra sprinkling of dried blood at 30g (1oz) per square metre/yard.

With greenhouse/dessert grapes, start feeding a month after growth starts in the spring with a high potassium liquid fertiliser, such as tomato feed, every two to three weeks. Once the vine is in full leaf, increase this feeding to weekly intervals. Stop feeding when the grapes start to ripen and colour up, as extra feeding at this time may spoil the flavour of the fruit.Removing flowers and fruit

Remove all flowers for the first two years after planting, so all the plant’s energy goes into getting well established.

Then allow only three bunches of grapes to grow on three-year-old vines, and about five on four-year-old vines – slightly more if the plant is growing well. Allow full cropping thereafter.

With dessert grapes, it is best to thin out the fruits within each bunch, to produce better quality grapes (see Extra care for greenhouse grapevines, below). The fruits of outdoor wine grapes do not need thinning. Extra care for greenhouse grapevinesVentilation and temperature

Grapevines like well-ventilated, warm, dry conditions. Although keeping the vents closed would raise the temperature, it would also increase humidity, which encourages fungal diseases and hinders pollination. So it’s best to keep the vents open during summer and autumn, especially around flowering and fruiting time.

Some varieties, such as ‘Muscat of Alexandria’, benefit from extra heat, so for these place a small fan heater in the greenhouse in spring (to aid growth) and in autumn (to aid fruit ripening).

In September, gradually remove the leaves to expose the branches to sunlight and improve larutan circulation.

In winter, don’t heat the greenhouse and do ventilate it freely in still, cold, dry weather until early spring, as dessert grapes need a period of cold to induce dormancy. Aiding pollination

Greenhouse grapevines may need help with pollination as there are fewer natural pollinators indoors. During flowering, at midday on a sunny day when the atmosphere is dry and the greenhouse is well ventilated, either shake the stems briskly but firmly, or stroke a cupped hand over each bunch of flowers, to transfer pollen between them. The latter is a more reliable method for early season Muscat-type grapes, where pollination can be sensitif. Thinning dessert grapes

The size, sweetness and quality of dessert grapes are improved by reducing the number of fruits within each bunch. Thinning the fruits also encourages even ripening and better enceran circulation, which discourages fungal problems.

Thin twice, first when the grapes are tiny and again when the grapes have increased in size.

Use scissors to thin the grapes – ideally vine scissors, which have long, narrow blades (available from some garden centres and mail-order suppliers). Steady the bunch with a small forked stick when thinning, as using your fingers spoils the bloom on the skins. 

Remove about one in three grapes per bunch. Bunches can also be shaped while thinning – aim to produce a perfectly proportioned conical bunch.

Afterwards, check the grapes two or three times a week and remove any that are diseased or damaged. Removing tendrils

Tendrils are thin, twisty stem-like structures that curl around supports to allow the vine to scramble and support itself. Remove these as they form, as they will only get tangled up with the fruits and allow the vine to scramble rather than sticking to your pruning and pembinaan regime. Diverting the plant’s energy reserves away from tendril production will also leave more energy for fruit production. Pruning and pelatihan grapevines

Grapevines are vigorous plants and if left to their own devices will soon outgrow their bounds, producing lots of lush leafy growth. So to keep them in check and maximise fruiting, they need to be trained on supports and pruned carefully. 

Grapevine are usually supported on a system of melintang wires, either attached to a wall or fence, or to large, sturdy posts: 

For vines against a wall/fence, space the mendatar wires 25–30cm apart (10–12in).

For vines in open ground, insert 2m (6½ft) posts, 60cm (2ft) into the ground, 3–tiga.6m (10–12ft) apart. The melintang wires should be spaced 30cm (12in) apart.

The main pruning time is early winter (late November to December). Training and pinching out of new shoots, as well as fruit thinning (see above), should be done in spring and summer.

In gardens, the most widely used pruning/pembinaan systems are:

rod and spur system (or cordon system), where fruiting side-shoots grow from a main vertical stem, like an espalier. This method is often used for grapevines growing in a greenhouse or against a wall outdoors

Guyot system, where young fruiting growth develops from one or two mendatar armsStandards – vines in pots or where space is limited can be pruned and trained as standards, with a tall clear stem and a rounded head, like a lollipop

For detailed advice on these pruning and pembinaan methods, see our guide to pruning and pembinaan grapes. Propagation

Vines can be propagated from hardwood cuttings in late autumn or winter. Softwood and semi-ripe cuttings can also be taken from late spring to mid-summer. Grapevines sold commercially are often grafted.

Named grape cultivars will not come true to type from seed, so seed propagation is best avoided.PlantChoosing a grapevine to plant

There are two basic types of grapes – dessert grapes for eating, and wine grapes, although some varieties may be suitable for both.

Dessert grapes are sweeter and need warmer temperatures to ripen properly, so for a successful crop they generally need to be grown in a greenhouse in the UK

Wine grapes can be grown outdoors in milder areas of the UK, but will crop better under glass

Within each category, there is a choice of varieties, offering white, red or black fruits, seeded or seedless, with different flavours, levels of sweetness, hardiness and resistance to disease. Take care to choose a variety to suit your climate and soil. Look in particular for those with an RHS Award of Garden Merit (AGM), which shows they performed well in trials – see our list of AGM fruit and veg.

Grapevines are usually sold in containers, as young plants 60cm (2ft) tall or more. They are widely available for most of the year in garden centres and from online suppliers. 

If buying in person, check plants to ensure they are healthy – if buying in summer, the foliage should be green, not yellow. Avoid plants that are ‘pot bound’ (with a mass of roots running round the inside of the pot). Where to plant

Grapevines can generally be grown outdoors in southern Britain, south of a line between Pembroke and the Wash, but it’s worth experimenting with growing north of this line, especially in western areas influenced by the Gulf Stream or in sites protected by a warm wall. Use later-flowering cultivars in northern areas. With rising temperatures due to climate change, the range of growing sites is ever expanding.