“We ought to do good to others as simply as a horse runs, or a bee makes honey, or a vine bears grapes season after season without thinking of the grapes it has borne.” – Marcus Aurelius
Grapes. It’s doubtful that a less understood or more under-planted fruit could be discussed with regards to northern gardens than the humble grape. While it’s true that the vast majority of the world’s grape varieties would be unimpressed to find themselves plunked into a northern garden, enough hardy varieties exist to ensure success for the gardener intrepid enough to wander down this particular path. After 8,000 years of cultivation, grapes have been bred to excel in nearly very imaginable garden scenario. And the good news is that growing grapes is actually a very easy and rewarding undertaking.
Grapes can be successfully grown in nearly any soil type but for the happiest vines a well draining soil is the best. Proper drainage can do so much to improve grape yields that you will often find vineyards, or even single specimens, planted on the sides of hills. This could be one of the most important decisions you make when trying to decide where to establish a grape vine in your home garden. The one aspect of northern grape husbandry that trumps all others, however, is micro-climate. As much as many grape cultivars are well suited for growing in colder climates, they still adore heat and sun. Planting grapes on a south facing slope or on the south wall of a building will go a long way to ensuring their happiness. Just remember that although you will likely be planting a little “stick” with roots, in just a few short years you could potentially have a monstrous plant. Grape vines quickly cover trellises, walls and even trees. They can also be quite heavy in late summer while in full leaf and bearing a crop of berries. Also, grape vines are incredibly long lived. A happy grape vine can easily surpass fifty years. With these two points in mind, be sure to plant your grape vines where they can remain undisturbed “forever” and where an adequate support system can be provided for them. Areas that are protected from winds are a bonus but grape vines do need good air circulation to keep moulds and mildews at bay. Full sun is imperative. Never plant grape vines where they will be shaded. I have one grape vine that was planted on a trellis beneath a maple tree over ten years ago. That grape vine comes back reliably every year but attains less than a meter of total growth each summer and has never borne a single cluster of fruit. I expect it will still be there ten years from now in an equally unhappy state of existence.
Grape vines do not need a particularly rich soil in which to grow. In the first year of establishment, most experts suggest that you don’t feed your grape vines at all. Some believe that a small amount of nitrogen at planting time can help your vine get a quick start. Since grape roots go extremely deep, very little fertilization will be needed once the vines are established. An organic fertilizer with the numbers 10-10-10 (or close) can be applied sparingly each spring around the base of the plant. Never give nitrogen to your grape vines after mid season or they may end up with an excess of lush growth going into winter and be extremely prone to damage. In the first season ensure that a regular watering regimen is maintained. In subsequent years, water deeply in times of drought, especially when the fruit is forming. The only other critical thing to get done in the first year is to build a solid structure around your grape vine that can support its future weight.
Grape flower clusters form on branches that grow from buds on last year’s wood. In extremely cold winters these buds can be damaged so many grape growers give their vines extra winter protection. Pruning grape vines can be as simple or as complicated as you’d like it to be. My most productive grape vine is actually one that is never pruned and has run rampant over a very large area. However, the literature on such matters does suggest that proper pruning has been proven to increase yields and since grapes grow so quickly out of control, annual fall or winter pruning is likely a good thing. It is generally accepted that removal of up to ninety percent of the vine is optimal. Prune with an eye to developing two or three lateral runners coming off each side of the main trunk. Trellis these at varying heights to ensure good airflow and sun penetration. For anyone who wishes to engage in serious grape vine pruning, there are plenty of Youtube videos available that examine the subject in great detail.
The only other thing you need to do to ensure success is to start with winter hardy varieties. For my money the sweet and large blue-fruited Valiant would be the best place to begin this spring. Have fun!