Transcript How to Prune grapevines

How to Prune Grapevines
Part One
Introduction
Pruning is one of the most important operations
carried out in the vineyard and is one of the most
expensive and time consuming
Introduction
Pruning time gives the opportunity to:
• Regulate the form and size of the vine
• Regulate the vigour of the vine
• Regulate the quantity (yield) and quality of the
grapes
It Starts in the Bud
The bud contains the shoot, the leaves,
tendrils and flowers, ready to burst and grow
in spring
A bud is found in the nodes of grapevine
shoots
These buds appear single but in fact, comprise
at least three 'true' buds and a lateral bud
Bud
Node
Shoots
Tendril
Leaf
• In spring the main bud
bursts to become a shoot
•
The shoot will produce
the flowers that
become the fruit
Flowers
Shoots
As well as producing
fruit for this season
the shoot develops
the buds for next
seasons growth
Later on the shoots
harden, turn brown
and become canes
The shoot……….
becomes the cane
Canes
• A shoot becomes a cane after periderm
formation
• From these canes will come the shoots that
will carry the crop for the next season
• But canes will only produce fruit if they come
from buds that have been left deliberately (if
you can count them)
• Otherwise....
They are Watershoots
The difference between a watershoot and a
count shoot is....
Watershoots
 Watershoots from
nowhere
 Count shoots from
count nodes
Therefore…
• Pruning is a matter of leaving count nodes
• Count nodes are the nodes that you
deliberately leave at pruning
• Count nodes are always from wood (canes)
that grew in the last season
• These canes come from count nodes from the
previous season
• They are not from watershoots
Recap……
• Nodes contain buds
• The main bud bursts to become a shoot
• The new shoot produces the flowers
which become the fruit
• At the same time the new buds are
forming in the shoot
• Shoots become canes when they turn
brown
• Only canes that come from deliberately
left buds are used for pruning which are
found on count nodes
Before we move on
 Blind buds
 Buds that don’t burst
 Basal bud
 A bud at the base of a
cane
 They don’t normally
burst in the same
season as buds at nodes
 These can remain
dormant for many
years
 But when they do
burst they produce....
Watershoots
• Watershoots
come from buds
that have been
dormant
• But during this
time they lose the
fruitfulness
• And that’s why
they look like they
come from
nowhere!
One last thing!
• Bud swell and bleeding
• Bud swell is when the buds swell and
become fluffy just before budburst
Bleeding
• When a cane, spur or cordon is cut close to
bud burst time the cut 'bleeds'
• Bleeding is due to increased sap flow within
the vine, which brings carbohydrate from the
roots and trunks
• It can also bleed early on in the pruning
season if it rains heavily followed by warm
weather
Next…..Cane Pruning