How to Grow Grapes

No other vine is more widely grown on our planet than the grape (Vitis vinifera). It’s hard to think of a world without wine; it has been part of religious and secular life for thousands of years. It is also hard to imagine an Australian school lunch box in February without a bunch of crunchy, sweet grapes. 

Not just edible, and fermentable, the actual grapevine itself can also provide cool summer shade and warm winter sunlight when grown over a north-facing pergola – a use that is both practical and beautiful.

Grapes are not fussy about their soil, but they are about their climate.  Grapes prefer a cool to cold winter with a wet spring. A long, dry summer is essential, mainly because they are prone to all manner of fungal diseases that require diligence, and plenty of copper sprays. It is essential to keep your vine open to air and sunlight to maximise crops and minimise disease. 

Grapevines have a deep and vigorous root system, which makes them very drought tolerant once established. However, vines should not be allowed to dry out when they are in flower, as this will drastically reduce the amount of fruit set. Once the fruit has formed, water moderately so as not to dilute the flavours. 

The dormant vine is very frost hardy, but the new shoots are vulnerable to heavy frost. All European grapevines are self-pollinating.

Many books have been written about training grapevines, but for most of us, we only need a few basic principles to grow healthy and productive grapes. Firstly, start with establishing and developing the main trunk. Start by selecting a vigorous shoot and train it to a stake or pergola support. In winter prune out all other growth until this stem is at the desired height. 

When this shoot reaches the point where you need it to branch, cut out the topmost buds to encourage growth sideways – these will become the main fruiting ‘arms’ or branches of your vine. Two such branches suit a vine on a trellis, four or more if you want to spread your vine over a horizontal area like the top of a pergola. Only once this stage has been reached can the gardener prune to induce fruit. 

Grapes are borne on new seasons growth that originated from buds formed the previous year. To put it simply, grapes must be pruned so that some buds formed in the previous spring are left to provide the next autumn’s crop. Almost 95% of the previous season’s growth is removed. Start by cutting out any weak shoots arising from the permanent branches and prune back the strong ones to two buds formed last spring leaving a 15-20cm stub. In spring these two buds will form the new fruiting growth. The following winter, prune off all the growth from the top bud and shorten the cane from the bottom bud back to two buds. Annually pruning is usually all that is required to keep grapes healthy and productive.