A good preparation is the key for success and sustainability

An appropriate preparation of the soil enhances a better rooting and growth of the vine.

Clearing or vine grubb-up

When clearing or grubbing up vine risk comes from virus diseases such as fan leaf or fungi like root rot to name a few and nematodes. Bear in mind that no cure is still available for root rot. Therefore it seems wise to act in a preventing manner improving draining conditions to limit water excess and avoid clearing oak plots, source of root rot. An efficient method to detect any virus diseases is to perform the ELISA test (fan leaf and leaf roll).

The aim of grubbing is to clear roots from the soil to limit any risk of contamination. It is advised to leave the soil resting for seven years between two vines planting. During the resting period a permanent cover such as barley which roots produce a substance that might delay root rot growth should be considered.

Grubbing up should be best carried out on a free of abnormal external moisture soil (not too moist, not too dry) using methods that extract maximum roots without moving soil horizons. A deep plough seems to have an undesired impact with horizons inversion which modifies the soil’s structure.

Partial killing of roots

The goal of this method is to avoid after grubbing survival of root fragments likely to shelter infectious material carriers of viruses or fungi.

Before grubbing up the parcel a partial killing of the vines just after the last crop a systemic a weed killer should be applied on the leaves. In this case grubbing will be postponed till next April-May.

Soil disinfection

This practice is link to positive results in nematologic analysis. After the withdrawal of products such as Metam Sodium wine growers are still waiting for new techniques and molecules.

Parcel landscaping

Landscaping is a great opportunity to review water and air flow management. Leveling process should be made with great care as noticed in sloped vineyards the excess of soil at the bottom due to torrential rains and seasonal rainfalls.

Leveling

This is a difficult process that should be planned on a dry soil due to the weight of the machines. The aim is to level the terrain enhancing water flows to limit erosion. Be cautious not to invert soil’s horizons to end up with unfertile layers on top which will certainly lead in a long term to a sterile soil.

Water scheme and erosion

Control water flow and avoid stagnant water

Few methods are available to manage water flow and limit erosion.

Sloped parcels

• Création de plateformes ou des banquettes pour casser la pente.
• Place rain collectors at the top of the parcel and ditches along it to control water flow. Building small walls at the bottom to hold the soil in place.
• Use natural controlled planting of grass to limit erosion
• Limit the length of vine rows
• Create flat areas like small terraces to break the slope

Stagnant water

Stagnant water is a real scourge because it may lead to vine hypoxia and is main source of virus diseases such as root rot, black rot or mildew which appreciate this kind of environment. Machinery access is also limited.

Means :

Set up an underground pipework. Use drains in terracotta or PVC tubes fill ditches with big stones. Avoid old fashion methods using vine shoots in faggots which can shelter root rot.

Cold and humid air flow management

A good air flow management can avoid extensive damage like frost, grey mould and fungal diseases.

A hedge or a wall are meant to cut upstream cold air flowing down and remains at the bottom of the parcel. This can limit spring frost. Also tall grass is a vector of air chilling and propagation. Natural barriers at the bottom of a parcel can contribute to air stagnation. To improve air flow it might be useful to clear bushes or cut hedges.

Wind

Strong wind can be hostile to vineyard leading breakage and dryness of the vine.

When a parcel is exposed to wind, hedges can be an alternative to protect it from the wind and decrease the drying effect which is beneficial during drought season.

Soil preparation

This is the last step is a key issue regarding root system development as well as planting success rate. A poor preparation may jeopardize the future of the parcel.

Loosening soil

During root system growing stage, young vines needs a 40 cm deep loose soil. To achieve this there are two methods:

Sub-soiling which enables soil cracking without horizon’s inversion and the deep tillage which reaches 80 cm deep and inverts soil. The latter is not recommended on chalky, bedrock and compact clay soils.

Leveling

Soil leveling takes place shortly before planting process starts and its purpose is to level the terrain removing big rocks and sometimes the vegetal cover. In order to avoid soil compacting it must be performed on a dry soil.