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SPRING AND SUMMER IN THE VINEYARD |
At this time of the year all the
effort is on summer maintenance. As April turns to May the buds burst, starting
as delicate pink blobs, which open out to form the young pinky-green shoots.
These grow rapidly, producing leaves, and tiny flower buds. The vines attempt
to form more buds than are wanted, particularly as so much of the top growth
has been pruned off, and with it most of the buds the plant was planning to
produce. In spring buds appear down the main stems, and also the root stock
will be trying desperately to propagate by putting up suckers (most of our
vines were grafted on to a different root stock from the main plant). In late
April/early May these unwanted buds are removed by brushing them off with a
gloved hand. The tractor work then begins with mulching the vine prunings. The
mulcher is like a large mower, but it chops up the grass and vine stems into
small pieces so that everything will rot down quickly and return as much
goodness as possible to the soil.
A young vine bud on the point of burst
In July the flowers burst forth,
but a vineyard in bloom is not quite as exotic as one might imagine because
vine flowers have no petals. Most vines are hermaphrodites and each flower
bears both the male and female sexes - hence they are self-pollinating. We
require good sunny weather without rain and just the gentlest of breezes for
pollination. Unfortunately at just about the critical time for us groups of
rain worshippers converge on a town called Wimbledon and engage in an ancient
rain-making ceremony, uttering heathen ritualistic sayings such as 'You must be
joking ref.!'
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A young shoot with a bunch of flower buds on it |
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A vine flower showing the central female pistil and the male stamens with their pollen caps |
After pollination the set flower
undergoes a tremendous transformation to become the mature berry - the grape.
Tractor tasks are:
- Spraying the vines to protect them from fungal diseases and
insects. The latter is not usually a problem except in years when the wasp
population is high. Fungal diseases are a problem in our damp climate, and
we always need to spray (unlike the Californians for example whose climate
is pretty well guaranteed hot and dry in the summer). We have a limited
range of chemicals we can use since all chemicals have to be approved by
DEFRA (Department for the Environment, Farming and Rural Affairs), and of
these the most useful is sulphur, which is cheap, relatively harmless, but
only works when the temperatures are above about 25 deg. C. Details of
vine diseases and their treatment is beyond the scope of this website, but
the main annual diseases we encounter are commonly referred to as Powdery
Mildew, Downy Mildew, and Botrytis. Untreated vines out in the open
are unlikely to fruit without our help, and although you may well have
come across Botrytis referred to as Noble Rot, which is
responsible for the wonderful sweet wines of Sauterne, Barsac and
elsewhere, it is very seldom in the appropriate form in England to do
other than rot the grapes as they reach ripeness.
- Mowing the grass. We have always used as little herbicide as
possible, because killing off the grass exposes the soil to erosion; makes
working conditions difficult as we are on a heavy clay soil which turns
readily to mud in the rain; and allows it to dry out too much in the sun.
Also a build-up of chemicals in the soil is ultimately bad for the vines.
- Applying herbicide (weed killer) in strips under the vines.
Although we restrict our use of herbicide we do spray the ground below the
vines to prevent the growth of weeds which would compete with them. If we
get the time of application just right it is possible to manage with just
one application of a herbicide such as Roundup, which kills of the
weeds, but does not go into the soil. The dead weed layer then forms a cover
for the whole season which keeps the soil moist, prevents the ingress of
weeds, and protects the topsoil against erosion.
- Trimming the vines. As the vines grow we tuck the shoots between
the wires on the trellis to form a hedge of leaves. These leaves are
essential to provide the energy the plant needs to grow and ripen the
grapes. However too much leaf growth hides the grapes from the sun and
prevents us getting the fungicide spray into the whole plant. Hence the
vines are trimmed with a specially designed tractor-mounted cutter to form
a neat hedge. The sketches below show the vine hedge before and after
trimming.
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As the season progresses preparations begin for harvest, but that is the
next part of the story.