Did you know that grapevines flowered? It’s not common knowledge, as the flowers are so tiny, they can’t really be seen. Flowering is (as with most crops) a very important part of the fruiting process – and for wine grapes in particular, flowering and the conditions during this period can have a marked effect on the fruit set – and ultimately on grape quality and even yield.
Flowering occurs in late spring, 6-8 weeks after budbreak (depending on rainfall and temperature), and in this stage pollination and fertilization occurs, leading to the cluster that will become a beautiful, healthy bunch of grapes. This process is very delicate – for example, excessive winds can interfere with pollination – and certain cultivars are more sensitive to these. Chardonnay is one such cultivar. If the flowering period is excessively windy, and the flowers sustain damage, this leads to a looser set cluster later in the season, which is not ideal for optimal quality.
To protect the vines and prevent this, the canopies are typically left closed until the end of flower set before they are opened up. The goal here is to prevent as many flowers from dropping unnecessarily as possible, by avoiding movement around the delicate tendrils. During the set period, we can also support the growth through adding very specific fertiliser – rich in magnesium, boron and manganese. Along with this, moisture in the soil is very important – not too little, not too much. This year has brought a moderate spring, with some cold and rain but not too much, leaving the vines in good shape for fruit set.
The different trellising systems we use on the farm also contribute to protecting – both bush vines and the echalas or stok-by-paaltjie vines are more protected against the wind, further minimizing potential damage. With a moderate Spring behind us, we are looking forward to a promising summer, with beautiful full bunches of grapes, ready to become our next prize vintage.