Pruning Bush Vine Grapes

In this post I will try to explain the process of pruning bush vines. It is very different from trellised vines, but the principle stays the same.

Firstly, pruning commences when the vines go into dormancy, which is during winter. The plant sheds its leaves and the processes in the plant came to a halt.

Before you start cutting away at a vine, there are some aspects to keep in mind.

Your first consideration must be the purpose of the specific block of grapes. Is this a bulk block, a reserve, a premium or ultra-premium block?

Secondly you must let the vine tell you how to prune it. It will show this through the vigor. A very vigorous vine is not in balance. This is your job to always maintain balance in a vine. Vigorous vines can be brought into balance through putting more bearers on. It is important to spread the bearers around the vine and not all to one side.

Thirdly when pruning you should consider the leaf to fruit ratio. This is actually controlled more during suckering, but the initial phase starts during pruning.

Okay, now to the practical part.

Let’s start off with first year plants.

(Pictures taken from "Wingerdbou in Suid-Afrika", page 203)

During the first winter pruning (B.) all the shoots are cut away, except the strongest one that is upright. This shoot is cut back to two buds. (can be three buds if the shoot is strong) Cutting back so drastically in the first year ensures that more growth goes into less shoots the following year, resulting in stronger arms and quicker development.

The vine should not ripen any fruit in the first two years. Any fruit should be cut off at an early stage. For the first three years we focus on vine development and not on production.

(Pictures taken from "Wingerdbou in Suid-Afrika", page 203)

During second winter pruning more bearer arms are left. We try to get at least five shoots on, depending on vine vigor. In the third year we will add another two or three, and we generally try not to go for more than eight bearing arms.

During the following years we try to maintain balance and from year six onwards you should try to leave renewal shoots to prevent excessive wood buildup, called "Candles".

This is just a basic description, but I hope it clarifies the basics of pruning a bush vine.