The Dombeya Scholarship
Dombeya Scholarship 2009- Ntando in Australia, Part 2
The picture above depicts how the vineyard blocks look like currently, it got me curious on why such effort in netting all the vines. Believe me it is they showed me how it's done! The main problem is the called the silver eye (a very small bird), it can cause much damage to berries. From veraison onwards as soon as the sugar starts to rise these birds flock in numbers attracted by the sugar and poke the grape berry which not only damages the fruit but causes VA, botrytis and a release of undesirable acetic acid which spoils the grape berries. For the red grape berries they can even be damaged as soon as they start to change colour.
To get back to Steve's philosophy, each year he plans to use less chemical control in their vines hence for example to control mealy bugs they use the lady bird as a natural predator for them, these lady birds either grow naturally or are bought and dispersed in the vineyard because they are so effective.
For powdery mildew, vine mites are sprayed with sulphur as a fungicide. Sprayed about 10 times through out the season over a 14 day interval on the leaves. For downey mildew copper is used. The secret though is Biofish (fish emultion) organic product added for natural leaf health. All the sulphur, copper and biofish are mixed together and sprayed at the same time. Organic / mulch compost instead of fertiliser is used to decrease nitrogen for plant nutrition as nitrogen enchances excessive vegetative growth.
The compost is also water saving as its stops evapouration because the mulch is banded along the vine. Once this organic environment has been created, the beneficial soil microbes thus have an aerobic environment in which they increase soil health, structure and nutrition. Sometimes calcium is sprayed just before bunch closure to stop botrytis.
If you look closely at the picture there's no cover crop because it's removed between November – December to make mulch for the next season as an organic matter. Cover crops are used to improve plant nutrition and natural habitat for the natural predators. Two types are used firstly, the clover (arrow leaf clove) and cereal rye they are alternated between the rows.
The clover helps with nitrogen fixing for the vine and it decreases the garden weevil because the weevil doesn't like the clover taste. The garden weevil eats up the berry cluster thus reducing shoot growth. The cereal rye is the second type used it's chosen because it serves as a wind breaker for the vine as it grows upright above the cordon wire to protect the bunches, this is especially useful for the young vines.
Other measures to stop the garden weevil is Dacron fiber which is sticky tape material which is plasted around the vine trunk it lasts for about 3 – 4 years. I can't give away everything at once just keep logging to Dombeya wines website to find out more.
On the last note South Africans are blamed everyday for bringing that silly garden weevil which spoils their beautiful vines (beautiful they are indeed)! And I on the other hand to make myself feel better about all the guilt they bestow upon me, I reply with the very wise words from Wikus Pretorious ( Dombeya's assistant winemaker/ viticulturist) 'remember the cricket!' Ouch no worries mate!
Click here to go to Dombeya Wines website.