1. TRELLISING OF GRAPEVINES INCREASING YIELD AND QUALITY
Andrew Teubes
Viticultural Consultant

2. 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

3. 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

4. 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

5. Mazar
Traditional bush vine
Afghanistan
Shomali

6. Traditional bush vine
Egypt
(Nile delta)

7. Traditional bush vine
Spain
South Africa

8. Traditional bush vine
Uzbekistan

9. 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 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)

10. Advantages of bush vines
Low cost
No expensive capital investment required

11. 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

12. Dust
Grape clusters very close to soil
Sun exposure – sun burn

13. 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

14. Management advantages
Clusters have protection
-sun
-dust
-physical damage
Comfortable height for working
and picking grapes
Easy control of weeds

15. Vertical Shoot Positioning (I-trellis)
South Africa
Chile

16. Semi Horizontal (Y-trellis)
Turkey
Mexico

17. Semi Horizontal (Double Gable)
South Africa

18. Semi Horizontal (Trentina)
South
Africa

19. Horizontal (T-trellis)
South Africa
Saudi Arabia

20. Pergola (Roof trellis)
Chile
South Africa

21. 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

22. Egypt
Reeds from Nile River is used as
trellising material

23. Afghanistan (Samangan region)

24. China Deep ditch plantation to resist winter freeze of roots
Close vine spacing to increase
vines per hectare
Deep ditch
plantation to
resist winter freeze
of roots

25. Uzbekistan

26. Comparison of performance of trellising systems (Chenin blanc/R99, 1980)
Treatment
Bush vines
Single
wire
Two
Three
Four
Wire
Five
1.5 m
Slanting
(5 wire)
Plant spacing
2.6 x
1.3
1.3 x 1.3
2.75 x
Plants/ha
2 959
5 917
2 797
Material costs
(Rand/ha) -
480
750
5.4 t
900
1430
1720
12.3 t
2400
Yield (ton/ha)
12.5 0%
22.9
26.1
27.5
220%
30.3
32.7
33.6
270%
42.6
Yield (kg/plant)
4.2
3.9
8.8
9.3
10.2
11.1
11.4
14.4
Income
R140/t)
1750
3206
3654
3850
4242
4578
4704
5964

27. 4.2 kg per vine
Bush vines pruned with short spurs

28. Single wire system
Post
Wire
70 cm
Soil surface

29. . Single wire trellis 8.8 kg per vine Shoot growth Wire position
Soil surface
8.8 kg per vine
Single wire trellis

30. Wire 2
30 cm
Wire 1
70 cm
Soil surface
Two (2) wire system

31. .
Soil surface
9.3 kg per vine
Two wire trellis

32. Three (3) wire system Wire 3 Parallel Wire 2 30 cm Wire 1 70 cm
Soil surface
Three (3) wire system

33. . . . Three wire trellis 10.2 kg per vine Position of parallel wires
Soil surface
Three wire trellis

34. Four (4) wire system Wire 4 30 cm Wire 3 Parallel Wire 2 30 cm Wire 1
Soil surface
Four (4) wire system

35. . . . . .
11.1 kg per vine
Soil surface
Four wire trellis

36. Five (5) wire system Wire 5 Parallel Wire 4 30 cm Wire 3 Parallel
Soil surface
Five (5) wire system

37. . . .
11.4 kg per vine . . .
Soil surface
Five wire trellis

38. Single slanting trellis
Wires
Single slanting trellis
5 wires
140 cm
Soil surface

39. Single slanting trellis. . . . .
14.4 kg per vine
Soil surface

40. 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