Martin Fish has vibrant grapevines after feeding
A balanced combination will give me a healthy harvest in autumn
The vine in my greenhouse is growing well this summer. It’s carrying a good crop of grapes and promises to provide us with a ripe harvest in September. The vine’s planted inside the greenhouse and the roots grow under a gravelled area where I grow a selection of citrus and ornamental plants in pots. Although I don’t water the vines as such, when I water the containers some of it goes onto the gravel, keeping the soil moist below. I suppose some roots also grow in the opposite direction outside where there’s plenty of moisture. However, now the vine’s in full growth and supporting around 40 bunches of grapes I’m going to give it some additional feed. Normally I’d give a high potash feed, but last year the vine showed signs of magnesium deficiency (yellowing between the vines), which can be caused by over feeding with potash. The high potash levels in the soil lock away the magnesium, making it unavailable to the plant. So it doesn’t happen again I’m going to give a more general feed with a balance of nutrients that I’ll water in through the gravel. To make sure the vine roots also have all the minor and trace elements, I’ll give a liquid seaweed feed as a tonic. The combination should encourage healthy growth and help the fruit to develop.
Summer pruning is something that needs doing little and often to prevent excessive growth being made and to divert the plant’s energy into the grapes. All I do is check over the vine on a weekly basis and any new long shoots are shorted back. Fresh growth made beyond the bunches is also trimmed back to two leaves. This will allow light to the bunches of grapes and help with the ripening process in a few weeks’ time.