Manual of techniques for sustainable mountain viticulture Josep Lluís Pérez Verdú

Manual of techniques for sustainable mountain viticultur

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In general terms, it is worth clearing as soon as possible, as it is considered pointless to allow bun-

ches to grow that are later to be thrown away. It is also used to remove the grapes formed on shoots

that have not reached optimum growth in order to increase the behaviour of the plant feeding these

shoots to ensure full growth the following year. Clearing is completed during veraison, with grapes with

a more compact morphology. However, Mas Martinet is experimenting on how the time and intensity

of clearing influences ripening and the likely alcohol content. Clearing may be designed according to

the alcohol content required (e.g. if clearing is moved to mid-September, when ripening is already well

advanced, skin ripening may be completed without significantly increasing the likely alcohol content). 

3.6. Synthesis of the basic control parameters

When Mas Martinet techniques are applied, the vigour of the vineyard stock, its production and the

quality of the grape are not left in the hands of the weather or soil conditions of each vineyard but can

be controlled using four forms of intervention by the vine grower (Figure 3.10):

•

Vine training and pinching (plant architecture).

•

Irrigation (or fertilisation).

•

Plantation framework.

•

Clearing.

Grape quality depends to a great extent on its morphology, which in turn depends on the plant archi-

tecture achieved through vine training. However, production depends on the intensity of clearing in

relation to the ELA of the stock, according to the type of wine to be produced. 

Within the plantation framework, the speed with which the target production is reached with the requi-

red quality can be controlled by the distance between stock on the same row. The distance between

rows, together with the plant architecture, determine the ELA/RSV ratio, i.e. the ratio between stock

demand and supply. The higher the demand in relation to supply, the greater the capacity to control

the weather and soil conditions to intensify or accelerate the processes or to slow down or stop them. 

The difference with more common cultivation methods lies in the way of balancing stock vigour with

plant architecture: 

•

In general, conventional methods are based (with no precise justification) on balancing down: irri-

gation is limited, fertilisation is limited, low fertility soils are sought, etc. until the stock vigour is low

enough to be distributed among the few shoots left on each vine. 

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Manual of techniques for sustainable mountain viticultur

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Figure 3.11 Vigour control techniques

to obtain quality grapes. Basic para-

meters and dependences

Vigour distribution

Vigour distribution

Irrigation precision level (R):

R1: lower

R3: higher

Vine grower’s intervention 

Plant architecture

ELA

Plantation framework 

ELA/PF

R1

Sugar synthesis 

Concentration

Reserves for 

the following year 

Transpiration-cooling

Transpiration-

cooling

Even ripening

Likely alcohol content

Quality grape

(basic wine quality) 

Grape

morphology

Vine training and pinching 

(controlling stock and no. of shoots)

R3

R2

Clearing

•

The vigour control method is based on balancing up: using vine training and precise irrigation tech-

niques to ensure the stock expresses all its varietal vigour for distribution among a much higher

number of shots. The method also has an added benefit the higher ELA/RSV ratio helps make ripe-

ning independent to the weather conditions. 

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Manual of techniques for sustainable mountain viticultur

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3.7. Additional techniques

3.7.1 Plant cover

Vines have traditionally been worked for two main reasons: 

•

To close off the evaporation channels formed in the soil in order to retain more water.

•

To remove weeds that compete with the stock for rainwater during growth periods and increase

the risk of blight.

Working the land also has certain disadvantages: 

•

It breaks up lumps of soil that protect the organic matter from aerobic degradation (Figure 3.12)

•

It creates surface mud that prevents water penetration and increases runoff and, with it, the risk

of erosion. 

An alternative to working the land used by some conventional plantations involves the application of

herbicides.

Under no circumstances do vigour control techniques consider working the vineyard, as they are per-

fectly compatible with the development of plant cover on terraces and on slopes. Plant cover does not

respond to an apparent need to reduce stock vigour, increasing the competition for water, but to the

notable benefits it provides

3

: 

Figure 3.12 Lack of physical protection for organic matter through working the land

Source: La degradación y desertificación de los suelos en España. Gas Natural Foundation. 2003

3

The use of plant cover is in line with European Union recommendations through the Common Agricultural Policy (CAP). More

specifically, the fight against erosion in fragile mediums promoted by the CAP encourages the following measure for the growth

of woody crops on terraces: “On plots with average slopes of over 10 % and soils with insufficient permeability, in order to avoid

run-off problems, plant cover must be established in the centre between rows, covering a minimum of 50% of the surface using

wild flora or planting cultivated species. The specific effects of run-off produced by torrential rain must be immediately correc-

ted.” (See Annexe II of Royal Decree 708/2002).

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