TRELLISING OF GRAPEVINES
INCREASING YIELD AND QUALITY
Andrew Teubes
Viticultural Consultant
In this presentation
• Different types of trellising systems used in
the world
• Factors influencing long term grape
fruitfulness
• Reasons for trellising or non-trellised
cultivation
• Advantages of trellising
• Comparison between yields of different
trellis systems
Grape fruitfulness
• Fruitfulness=potential of vine to yield fruit
• Two main factors
– Sunlight on leaves of basal buds during spring
period, especially during flowering and fruit
set
– Temperature during flowering and fruit set
• Any trellis system that will increase the
sunlight exposure of the leaves will result
in increased fruitfulness
Types of trellis systems
• Bush vines (traditional) – no trellis
• Vertical Shoot Positioning (VSP) – I-trellis
• Semi-horizontal Shoot Positioning
– Y-trellis
– Double Gable
– Trentina (Factory roof)
• Horizontal shoot positioning
– T-trellis
– Pergola (Spanish Paron, Roof system)
• Unconventional systems
Traditional
bush vine
Afghanistan
Shomali
Mazar
Traditional bush vine
Egypt
(Nile delta)
Traditional bush vine
Spain
South Africa
Traditional bush vine
Uzbekistan
Why bush vine and not trellis?
• Reasons for bush vine cultivation
– Soil potential medium, therefore do not expect
high vigour in plants (shoot growth stops
naturally at 70-80 cm)
– No irrigation or Low availability of irrigation
water
• Bush vines naturally yield smaller crops than
trellised vineyards
– No capital available for installation of trellising
materials (poles, wires, anchors)
Advantages of bush vines
• Low cost
– No expensive capital investment required
Disadvantages of bush vines
• Low yield potential
– Not suitable for cane pruning (increased bud load)
– No support for shoots under high vigour situations
• Disease control not effective
– Poor penetration of sprays into canopy
• Weed control very difficult (only by hand)
• Grape clusters have lower quality
– Temperature of clusters higher close to soil surface
– Physical damage to clusters close to soil
– More dust on clusters
• All labour activities problematic
– Pruning, shoot removal, leaf removal, harvesting
Grape clusters very close to soil
Dust
Sun exposure – sun burn
Advantages of trellising
• Vine has natural climbing growth habit; trellis
provides larger surface area for growth and
fruiting
• Increase yield potential
– Allows differential pruning techniques (spurs and
canes)
• Increase quality of fruit
– Above soil surface, no dust or physical damage
– Better micro climate around clusters
• Easy management and mechanization
– Weed control
– Disease- and pest control
– Labour
Management advantages
Clusters have protection
-sun
-dust
-physical damage
Comfortable height for working
and picking grapes
Easy control of weeds
Vertical Shoot
Positioning
(I-trellis)
South Africa
Chile
Semi Horizontal (Y-trellis)
Turkey
Mexico
Semi
Horizontal
(Double
Gable)
South Africa
Semi Horizontal (Trentina)
South
Africa
Horizontal
(T-trellis)
South Africa
Saudi Arabia
Pergola
(Roof trellis)
Chile
South Africa
Unconventional systems
• When are they used?
– When trellis materials are not available or too
expensive (poles, wires)
– When climatic factors limit the use of
conventional systems
• Continental climates with extreme winter chilling
– Vines must be covered with soil in winter to protect from
freezing
• Parts of Northern China, old USSR, Afghanistan,
Korea
Egypt
Reeds from Nile River is used as
trellising material
Afghanistan
(Samangan
region)
China
Close vine spacing to increase
vines per hectare
Deep ditch
plantation to
resist winter freeze
of roots
Uzbekistan
Comparison of performance of trellising systems
(Chenin blanc/R99, 1980)
Treatment
Bush
vines
Bush Single
vines wire
Two
wire
Three
wire
Four
Wire
Five
Wire
1.5 m
Slanting
(5 wire)
Plant
spacing
2.6 x
1.3
1.3 x
1.3
2.6 x
1.3
2.6 x
1.3
2.6 x
1.3
2.6 x
1.3
2.75 x
1.3
Plants/ha
2 959
5 917 2 959
2 959 2 959
2 959
2 959
2 797
Material
costs
(Rand/ha)
-
-
480
750
5.4 t
900
1430
1720
12.3 t
2400
Yield
(ton/ha)
12.5
22.9
26.1
27.5
30.3
32.7
33.6
42.6
Yield
(kg/plant)
4.2
3.9
8.8
9.3
10.2
11.1
11.4
14.4
Income
(Rand/ha
@ R140/t)
1750
3206
3654
3850
4242
4578
4704
5964
2.6 x
1.3
0%
220%
270%
4.2 kg per vine
Bush vines pruned with short spurs
Single wire system
Post
70 cm
Wire
Soil surface
Shoot growth
.
Wire
position
Soil surface
8.8 kg per vine
Single wire trellis
Wire 1
70 cm
30 cm
Wire 2
Soil surface
Two (2) wire system
.
.
Soil surface
9.3 kg per vine
Two wire trellis
Wire 2
Parallel
Wire 1
70 cm
30 cm
Wire 3
Soil surface
Three (3) wire system
..
.
Position of parallel wires
10.2 kg per vine
Soil surface
Three wire trellis
30 cm
Wire 3
Wire 2
Parallel
Wire 1
70 cm
30 cm
Wire 4
Soil surface
Four (4) wire system
.
..
..
11.1 kg per vine
Soil surface
Four wire trellis
Wire 4
Wire 3
Wire 2
Parallel
Parallel
Wire 1
70 cm
30 cm
30 cm
Wire 5
Soil surface
Five (5) wire system
..
..
..
11.4 kg per vine
Soil surface
Five wire trellis
140 cm
Single slanting trellis
5 wires
Wires
Single slanting trellis
.
14.4 kg per vine
Soil surface
.
.
.
.
Summary
• Trellis systems will always increase yield potential,
because
– Creates larger area for vine to grow
– Allows better sunlight penetration into canopy,
increasing fruitfulness
• Long term high yield will only be sustainable
together with
– Correct pruning practices
– Effective summer shoot management (shoot thinning,
shoot positioning, leaf thinning)
• Regular maintenance of trellis sytem