Preparing the planting of vines
Planting a vineyard plot is a long-term investment. The choices made at each stage of the planting project often have significant consequences on the sustainability and profitability of the plot, or even the entire farm. It is therefore essential to anticipate and carefully prepare each planting operation.
Certain observations and analyses can help secure decisions, whether it is to guide the plot development and soil preparation work, to properly plan the base fertilization, or to choose the most suitable plant material. Here are some key points to successfully plant your vineyard plot.
Anticipate and plan the work
A vineyard planting project should be planned at least one and a half to two years before the actual planting. This allows for the necessary observations and analyses, anticipating the order of plants, and carrying out the preparation work on time.
Detect the presence of grapevine fanleaf virus and black-foot disease
These diseases are incurable and are transmitted by pathogens sometimes present in the soil that develop on the vine roots. They can contaminate new plants, condemning them to die in the medium or long term.
Grapevine fanleaf virus
This is a virus transmitted by a nematode, at the level of the roots, affecting yield and longevity of infected vines. Symptoms:
- stunting of the vines
- shortening, deformation and fasciation of shoots (flattened, zig-zag)
- deformation and discoloration of leaves (mottling) or even complete yellowing
- shatter, millerandage, yield losses
Laboratory analysis can confirm the diagnosis.
If grapevine fanleaf virus is present, it is recommended to:
- devitalize the plot
- extract as many roots as possible
- plan a long soil rest (ideally 7 years) before replanting
Black-foot disease
This is a disease caused by a fungus that develops on the roots, leading to the death of infected vines. This pathogen is often found on plots with previous crops of oaks or trees fruit trees. Symptoms:
- decline of vegetation
- weakened shoots
- coloration of the leaves (yellow on white grape varieties and red on black grape varieties)
- foot infections in circles in the plot ("black-foot rings")
Note that the symptoms of black-foot disease are similar to those of esca.
If black-foot disease is present, it is recommended to:
- carefully uproot the vines
- extract as many roots as possible
- drain wet areas as much as possible
- limit water accumulation on the plot
Characterize the plot and soil
Before starting planting, it is essential to understand the properties of the plot: environment, previous crop, soil and subsoil. This characterization allows adapting the plot development and soil preparation work, the choice of plant material, and the vine layout.
Observation first
Several criteria useful for planting preparation are fairly easy to access:
- topography: altitude, slopes, exposure, water accumulation zones...
- environment and/or previous crop: presence of trees (competition, risk of black-foot disease...), other crops, etc…
Soil analysis, a crucial step
Physico-chemical soil analysis is a classic tool providing several indicators of the soil's agronomic and nutritional potential:
- Soil texture (particle size distribution)
- pH
- Total limestone
- Active limestone
- Chlorosis risk index
- Content in organic matter
- Soil biological activity
- C/N ratio
- Microbial biomass
- Cation exchange capacity (CEC)
For planting preparation, it is recommended to take two series of samples, with an auger, on each homogeneous zone of the plot:
- one series at 30 cm depth, for analysis
- one series at about 60 cm, for analysis
Soil analysis will allow, if necessary, to adjust the soil pH, add the necessary compost, or make a reasoned choice of plant material.
Soil pit as a complement
The soil pit provides more details on soil structure, subsoil, and physical constraints that could hinder root development of young plants. Its study informs on:
- The soil depth and different horizons
- The texture of each horizon
- The presence of rock horizons, crusts, compacted zones, hydromorphy...
- The distribution of the root system of the previous crop if any
The results of the soil pit allow anticipating plot development and soil preparation work, considering the planting direction and the most suitable plant material.
Choice of plant material
Criteria to consider when choosing plant material are:
- Grape variety and clone
- Water supply (soil, weather)
- Exposure and slope of the plot
- Vigor potential, precocity, maturation needs
- Sensitivity to decline
- Category of wine desired
- Regulatory constraints
- Market demand
- Rootstock
- Active limestone, IPC (risk of iron chlorosis)
- Water supply (dry soil, hydromorphy...)
- Vigor and precocity conferred (yield control, sanitary quality and maturation)
Prepare the plot for planting
The year before planting is the opportunity to set all favorable conditions for good rooting and development of young plants.
Uprooting the previous crop
Plot preparation begins with careful uprooting of the previous crop. When it is vines, it is recommended to:
- in case of fanleaf virus or black-foot disease, devitalize the vines after harvest (year n-2), with a glyphosate-based herbicide, thoroughly covering the foliage (except organic plots)
- prune the vines when dead
- the following winter, uproot the vines, when the soil is well dried and extract as many roots as possible
Do not keep the vines too long on the plot to avoid wood diseases.
Develop the plot
In most cases, developments are to be considered to improve the hydrological configuration of the plot, promote water supply to the future vineyard, and limit soil erosion in the plot.
Plot development is carried out in several steps, according to previously identified needs:
- By digging ditches on plot edges (grass strips, maintenance)
- By creating gentle slopes from the middle to the edges of the plot
- By installing a drainage system, only on plots with significant water excess, impermeable and deep soil, and suitable topography for drainage function
- By leveling or terracing the soil in case of steep slope, etc...
To prevent Soil erosion, it is recommended to:
- Plant perpendicular to the slope direction, when possible
- Establish hedges or preserve existing hedges
- Create slope breaks
- Avoid planting too long rows when the slope is steep
- Add organic amendments to improve soil structure
Prepare the soil
Soil work before planting aims to improve soil condition and eliminate large physical obstacles, so that young plants root well in the soil. Soil pit studies help guide the type of work to be done: objectives, depth, tool. In all cases, the soil must be well dried but not too dry to be workable.
Tools
Principle:
Objectives:
- Loosen, crumble the soil
- Extract roots
- Bury a cover crop
Advantages:
- Possible root extraction
- Soil loosening
Disadvantages:
- Mixing of soil horizons
- Smoothing or "plow pan"
Principle:
- Soil shattering
- Deep fracturing
Objectives:
- Break compacted horizons
- Fracture moderately deep crusts
Advantages:
- Respects soil horizon succession
- Facilitates soil drainage
Disadvantages:
Principle:
- Soil shattering
- Medium depth fracturing
Objectives:
- Slightly loosen the soil
- Decompact superficial horizons
- Clean soil after uprooting
Advantages:
- Soil loosening
- Respects soil horizon succession
- No smoothing
Disadvantages:
- No root extraction
- Expensive
- No effect on crusts
Principle:
- Soil reworking
- Shattering at shallow depth
- Raking effect
Objectives:
- Loosen and level the soil
- Superficially shatter the soil
- Fracture a very superficial crust
Advantages:
- Soil reworking just before planting
- Total loosening
- Respects soil structure if not repeated
Disadvantages:
- Little root extraction
- Limited working depth
Soil rest and recommended cover crop
Plot preparation work can disrupt soil structure and function. When possible, it is recommended to let the soil rest for at least 2 or 3 years before replanting (or up to 7 years in case of fanleaf virus or black-foot disease).
During this rest period, planting a cover crop promotes soil restructuring: the root system of grasses, crucifers or mixtures can decompact the soil deeper than a soil tillage tool. For this, the soil must be allowed to rest at least 3 or 4 years. This cover crop also provides good soil protection against Soil erosion. Finally, it becomes an interesting source of organic matter when incorporated before planting.
Apply base fertilization
It is much more practical to apply an amendment when the plot is not yet planted. Base fertilization should be based on soil analysis results and mainly consists of increasing the content of organic matter and correcting the soil pH.
Correct soil acidity
In viticulture, it is preferable that the soil pH is above 5.8 (otherwise: risk of metal toxicities, affected structure, blocked biological activity…) Correction of acidic soils:
- liming amendments or calco-magnesium amendments
- 3 to 7 tons of calcium carbonate/ha depending on the pHeau value
- at least 6 months before planting
- incorporate with plow or chisel
Improve organic matter content
Adding organic matter is often recommended before planting. In the Mediterranean region, the target rate is between 1 and 2%. Organic fertility management:
- Organic amendments, preferably plant-based and composted (especially on acid soils)
- Massive inputs, to be reasoned according to the objective and nature of the amendment
- at least 3 months before planting
- incorporate superficially: 20-30 cm maximum.
Always anticipate acidity correction a few months before organic matter inputs
Mineral elements
Except in case of proven deficiency, most mineral element inputs are made on established vines. However, phosphorus, potassium or magnesium inputs before planting sometimes compensate for strong deficits revealed by physico-chemical analyses.
The D-day
- Beforehand: calculate the number of plants (planting density, taking into account turnrows); choice of grape variety, clone and rootstock; last superficial plowing pass.
- Reception of plants: check the label, transport document, plant quality (hardening state, graft quality, root freshness).
- Storage of plants: limited to a few days, in the shade, rehydration (grafted-welded) or frequent watering (potted plants), or refrigeration.
- At planting: choice of technique (hole, auger, machine…), choice of stakes (metal, wood, diameter), taking into account turnrows (>7m); well dried soil, fine earth spread around roots, water settling (10 l/plant).
The goal is to:
- properly contact roots and fine earth around the plant
- avoid air or water pockets around roots
- avoid bending roots
- avoid soil smoothing around roots.
Source
- This article was written based on the PDF document "Vineyard planting: Proper soil preparation" published by the Chamber of Agriculture of Var.
Appendices
S'applique aux cultures suivantes
