Spring; high alert
Bud-burst: first Merlot, then Shiraz, then Cabernet Sauvignon. The buds which developed at the end of the previous season start to swell, their outside cases open to reveal a soft woolly protective layer, then the new shoot appears. The whole vineyard appears to be covered in a green haze. As the temperatures increase. the rate of growth goes up, and the green fuzz becomes a bright green mid-air carpet of small new leaves and tender, green canes.
This is the vineyard at its most vulnerable. The young shoots and leaves are highly susceptible to mildew and are extremely brittle. Too much rain, and the mildew will defeat the spray programme. Not enough rain and growth will be poor, leading to possibly low yield and/or lower sugar levels than desired.
Frost and hail are the worst fear. A single night of frost during the first two weeks after bud burst can wipe out the whole year’s crop. A brief hailstorm any time during the first several weeks can wreck havoc, knocking the new shoots to the ground. The vines will survive these traumas, throwing out secondary shoots with which to stay alive, but there will be very little fruit for the vintage.
There is not much that can be done to avoid frost, but we try to keep the mid-row grass short so that cold air can more easily flow down hill during the coldest part of the night, and not linger around the vines.
October- November