PRUNING SYSTEMS FOR GRAPE VINES

Andrew Teubes VG Nurseries

In this presentation

• Pruning objectives • Grape fruitfulness • Types of pruning

– Spur – Short canes – Long canes

• Practical use of pruning systems

Objectives of pruning

• Controlling the size and structure of the vine

• Regulate crop size • Maintain a balance between vegetative

growth and fruiting – maximizing the yield potential while

maintaining the health of the plant

Fruitfulness of grape vines

• Fruitfulness depends on – Grape variety (genetic) – Foliage management (summer practices)

• Sunlight penetration into canopy during and after flowering

• Fruitfulness involves the number of clusters per bud as well as the weight of the clusters

Permanent trunk (3 years or more)

Spur of previous season (2 years)

Shoot from this season (1 year)

FRUITFULNESS: 1 year old on 2 year old = fruitful (carry clusters)

1

5

10

14

Natural fruitfulness increases from the

basal position to the apical position

Flame, Victoria

Redglobe, Autumn Royal

Thompson Seedless, Dauphine

00.10.20.30.40.50.60.70.80.9

1 2 3 4 5 6 7 8 9 10 11 12

SUNSHADE

Bud fruitfulness of Thompson Seedless canes as a function of bud position

Node position on cane

Num

ber o

f clu

ster

s pe

r nod

e

Pruning types • Short spurs/bearers (2 buds)

– High fertility cultivars on cordon trellis – Flame Seedless, Victoria, Dan-ben-Hannah,

Alphonse Lavalleé • Half-long/short canes (5-8 buds)

– Medium fertile cultivars – Red Globe, Autumn Royal

• Canes (10-14 buds) – Low fertility cultivars – Thompson Seedless/Kishmish

Productivity of Sauvignon blanc as a function of pruning technique

Pruning method

Clusters /vine

Cluster weight (gram)

Total weight/

vine (gram)

2 bud spurs 20.2 63 1273

4 bud spurs 31.7 65 2061

Canes 38.5 79 3042

Spur pruning • Used for varieties that shows high enough

fruitfulness on basal buds • Vine structure is permanent cordon system • Shoot positioning normally vertical (VSP) or at

angle (Gable, Y-trellis) • Spacing between spurs of 12-15 cm important

– Sunlight penetration – Space for the clusters

Length of spur is 2 clearly defined buds

CORRECT SPACING

12-15 cm

Spacing between spurs result in good sunlight penetration and spacing of clusters

12-15 cm

Clusters well spaced, not touching each other

Well spaced clusters on spurs

WRONG SPACING

Results of poor spacing

No lignification of shoots

Low crop levels

Poor spacing of spurs

= No sunlight in canopy

Dead shoots

Results of poor sunlight in into canopy

Cane pruning • Used for varieties with low natural fruitfulness on basal

buds (1-3) • Vine structure consists of permanent trunk with annual

renewal canes • Shoot positioning can be vertical or horizontal • VERY IMPORTANT: For every one (1) cane that is

pruned, one (1) 2 bud spur must also be left below the cane for renewal

• Length of cane depends on the position of highest bud fruitfulness – Bud 5-8: Short cane – Bud 9-14: Long cane

2 year old cane from previous season

1 year old cane from this season

Canes in the field

How should it be pruned??

Spur for renewal

New cane

Principle of cane pruning

NOTE: The spur is always below the position of the cane

CORRECT CANE PRUNING

Spur of previous season in correct Position below cane

Short cane of previous season

Fruiting canes of this season

Cane for spur pruning this season

CORRECT CANE PRUNING

Spur for renewal

New cane

WRONG CANE PRUNING

Short cane of previous season

No spur at the base of the cane for renewal ??

Cane pruning in practice

Spurs

Canes

Cane pruning in practice

Cane

Spur

Well spaced clusters on canes