Grapes

Climate and soil

The Mediterranean environment is great for cultivating grapes. The hot, dry season is when the vines in their native habitat flourish and bear fruit. Vine growth occurs vegetatively in South Indian conditions from April to September, followed by fruiting from October to March. Optimum temperature is between 25°C and 32°C. Although the grape is broadly adapted to a variety of soil types, its yield and quality are greatest on excellent fertile soils with a pH range of 6.5 to 8.5, organic carbon content of at least 1.0%, lime-free, and having a medium water holding capacity.

Land Preparation
A tractor or bulldozer is used to level the land depending on the necessity, soil type, and gradient. For drip irrigation, levelling is not strictly necessary. In certain instances, seed, soft wood cuttings, layering, grafting, and budding are also employed to produce grapes, which are typically propagated through hard wood cuttings. Typically, pits are used to plant the grapevines. The distance between the vines as well as the particular needs of the variety affect the pit's size. Dependant on the kind of soil, the depth might range from 60 to 90 cm. In certain instances, seed, soft wood cuttings, layering, grafting, and budding are also employed to produce grapes, which are typically propagated through hard wood cuttings.
Seed rate and spacing
Depending on the soil type, variety, and training method, planting spacing is maintained. With vines ranging in density from 2000 to 5000 per hectare, the spacing between two rows may be 2 to 3 m, while the gap between vines within a row will be half that.
Crop nutrition management
Crop nutrition management
Irrigation Management
Irrigate as soon as the seeds are planted, on the third day, and then once a week. Irrigation should be stopped 15 days before pruning and 15 days before harvest.
Weed management
It is recommended to use Glyphosate @ 2kg/ha or Diuron at a rate of 3.5 kg per hectare. To prevent drift, it is important to apply herbicides to grapevines carefully and using a low pressure nozzle.
Intercultural operation

Gap filling: Filling up gaps should be done ideally within a month of planting.

Recut: One month after planting, a basal cut is made while maintaining 2/3 of the buds in order to promote uniform new growth.

Supporting: Young growth points are trained on the bamboo supports, which are attached for vine support.

Weeding: Depending on the amount of weeds, the vine rows are weeded twice or three times.

Irrigation: Regular irrigations are recommended depending on the soil and season.

To speed up the growth, fertiliser is administered when making slurry with cows.

Depending on the prevalence of pests and diseases, the appropriate plant protection measures are taken.

Insect pest management

Stem girdler: Sthenias grisator          

  1. To stop producing eggs, remove loose bark while trimming.
  2. Gather and eliminate the damaged plant parts.
  3. Use Carbaryl 50 WP 2g/lit to clean the trunk.
  4. Any of the following pesticides should be sprayed, with the first round applied just after pruning and repeated two to three times: Carbaryl 50 WP 0.1%, Phosalone 35 EC 0.07%, or Quinalphos 25 EC 0.05%.

Flea beetle: Scelodonta strigicollis

  1. When trimming, remove the loose bark to stop the hatching of eggs.
  2. Shake the vines to release adult beetles, then gather them in trays with kerosene water and kill them.
  3. After trimming, use the pesticide Phosalone 35 EC 0.07%.

Mealy bug: Maconellicoccus hirsutus

  1. To exterminate the ants, sprinkle 20 kg/ha of Quinalphos dust on the soil.
  2. Spray fish oil rosin soap at a rate of 25 g/lit together with dichlorvos 76 WSC at a rate of 1 ml/lit.
  3. Release 10 Cryptolaemus montrouzieri coccinellid beetles per vine.

Thrips: Rhipiphorothrips cruentatus 

  1. Gather and discard any damaged fruits, flowers, or leaves.
  2. It is advised to use one of the insecticides, Dimethoate 30 EC 0.06% or Methyl Demeton 25 EC 0.05%.

Berry plume moth: Oxyptilus regulu

  1. Gather the diseased leaves, destroy them, and then bury the remains in the ground.
  2. The pupae will be killed by summer ploughing.
  3. Pheromone traps can be used to draw in males and kill adults.
  4. Acetamiprid should be used locally to effectively manage this pest.
Plant diseases management

Downy mildew

To manage the disease, apply Metalaxyl + Mancozeb 0.4% or Bordeaux mixture 1%.

Powdery mildew

To manage the disease, apply Inorganic sulphur 0.25%, Chinomethionate 0.1%, or Dinocap 0.05%.

Bird’s Eye Spot / Anthracnose

Twigs that are infected need to be removed.

It is recommended to use Mancozeb 0.25% or Copper Oxychloride 0.2%.

Harvesting & post-harvest management

The typical grape harvest season begins in February and lasts until the end of April. Well-developed bunches with 18° degree Brix level are harvested.

Corrugated boxes weighing 2 to 4 kg are used to store harvested grapes. For marketplaces that are far away, grape guards and pouches are stored inside the boxes. Cold storage and export markets require pre-cooling and the usage of grape guards.