In the Mediterranean basin peppers are planted in the summer in order to be able to harvest in the fall-winter season. Following are some recommendations for plant care and maintenance in the early stages of the crop. It is important to build a strong plant before allowing pollination to take place.

Light Radiation and Temperature: Peppers grow best when they have the proper amount of radiation for photosynthesis and the optimum level of radiation is 800-1200 micro-Einsteins. If there is less light than this the photosynthesis is reduced and pepper production will be lower. It is for this reason that we always try and keep the plastic and net roofs clean especially in the winter months. 

Structures: Both greenhouses (GH) and nethouses (NH) are used for growing the winter pepper crop. The nethouses are of 25 or 50-mesh net depending on the insect pressure. The former has better aeration but allows more insect to penetrate the structure and the latter is called insect-proof net even though thrips can pass through. The GHs usually have 25 or 50 mesh net on the sides. The nets should be clean to allow for maximum aeration when planting. Afterwards, roofs and sides should be cleaned periodically to maintain good ventilation and higher light radiation in the winter months.   In the winter if the GHs have plastic curtains then they can help maintain warmer temperatures in the morning and late afternoon. This simple method can help increase the average 24-hour temperature by a few degrees.

Plant Stand & Density: Double rows are recommended with 50-60cm distance between rows in the same bed and the center of the beds is 1.4-1.6m apart. The distance from plant to plant within the row is 30-40 cm. Plant population varies from 32,000 to 40,000 plant/ha.    

Trellising and Plant Care: The Spanish method is used and there is no need to remove any side branches. Nylon string is used in conjunction with strong stakes or poles every 4m to keep the plants upright at all times. It is important to tie on time as delays can damage the plants and fruit. Zeraim Gedera varieties can also be grown using the Dutch method with two stems.

Additional Shading: A second black net giving 40-50% shade is maintained over the newly planted seedlings for approximately one month depending on the variety, crop location, weather conditions and plant development. The extra shade helps the plants overcome the very high summer temperatures by reducing the heat and light intensity and allows the plants to become established more quickly.. This encourages vegetative growth and together with flower removal (next paragraph) helps build a strong plant, which will be able to set a high fruit load and then carry it over the winter period and the life of the crop. In the winter after there is no more pollination and fruit set shading is used again to protect fruit from sun scorch. 

Flower Removal: Flower removal helps build a strong plant because the plant can concentrate on vegetative growth. It is recommended to remove the flowers at the first 3 or 4 nodes (0,1,2 and sometimes 3). Many will fall by themselves because of the heavy shading. Nevertheless, there will be many flowers that will have to be removed manually both while the shade-cloth is spread and then when it is removed.

Honeybees and bumblebees & Shaking flowers can help result in better pollination and fruit set. After the black shade net has been removed the bees can be introduced and/or the shaking of the plants by air blasting or by knocking the trellising can begin. Improved pollination and fruit set results in heavier and better shaped fruit. 

Removal of malformed Fruit: When the flowers begin pollinating there will be malformed as well as good fruits being formed. The misshapen fruits should be removed. This is a process that continues as long as pollination continues. There should be 6-10 good fruits/plant on the first flush of pollination so that there will be an even spread of the yield over the life of the crop.

Irrigation: It is recommended to use tensiometers to help determine the quantity and frequency of irrigation. Quantity and frequency vary with soil, climate and the condition of the crop.

Calcium and magnesium should always be present in the irrigation water. The calcium is applied at a rate of 80-120 ppm and the magnesium at 40-60 ppm.

Micronutrients: It is recommended to apply a chelated micronutrient mix to the crop either on a daily basis or a weekly basis. There are many mixes on the market and the manufacturer’s recommendations should be followed.

Table: Proportionate feeding of ZG peppers

Table: Grams/ha/day of N:P:K in a pepper crop