Lettuce Farming in South Africa from Seedlings: What to Know
Lettuce is in high demand throughout the year, as it is one of the main ingredients in most salads. Whether used as part of garnish, on burgers or sandwiches, or as the bulk of a green salad, the vegetable is an exceptionally popular vegetable in South Africa. Farmers now mostly grow the crop from seedlings they purchase from bulk-supply commercial nurseries.
By farming the crop from seedlings, the farmer does not have to invest in seeds and be concerned about seed germination rates or early stages of growth and pest problems. The plants are in the soil for a shorter period, whereby the farmer also saves money on pest and disease control, irrigation, and nutrient provision. The shorter period from planting to harvesting helps to reduce the risks associated with crop farming.
With the extreme temperatures experienced in South Africa, together with periods of drought, excessive raining, winds, and frost, outdoor propagation of lettuce from seedlings seems to be challenging at best. To reduce risks, ensure year-round production capacity, and increase yield success, lettuce farming in netted or greenhouse facilities is often recommended.
These facilities provide protection against many types of pests, minimise the risk of foliage damage because of birds, and reduce the need for excessive watering because of exposure to high heat and severe sunlight or hail. The temperature fluctuations can be better controlled, while the plants can be protected against frost. However, these facilities are expensive to set-up.
Newcomers to lettuce farming in South Africa should first determine if they have enough capital for the initial high setting up cost of netted or greenhouse facility growth, soil preparation, purchase of seedlings, and construction of adequate cold storage facilities after harvesting has taken place.
They should also invest in proper pest- and disease-control agents, nutrition for the plants, moisture metres, and pH measuring equipment. Also keep in mind that harvesting is labour intensive, even with mechanical harvesting methods used. A last consideration to keep in mind for entering the world of lettuce crop farming is whether the farmer has a definite market. This is important, as lettuce does not have a particularly long shelf-life and must be delivered to the market as soon as possible after harvesting.
The yield potential depends on the variety of lettuce seedlings planted, spacing, irrigation, pest and disease control, humidity levels, soil conditions, and more. Greenhouse-based production has the potential of delivery three or more times the harvest than is possible with open field production.
Planting and Spacing
The spacing requirements differ according to the variety, whether planted in a greenhouse or in the open field. Generally speaking, the farmer should be able to plant 120 000 or more seedlings per hectare. The period from planting to harvesting also differs according to the variety. Fortunately, it is a quick growing vegetable, ensuring a short production period. Drip irrigation has been proven to the be the best watering method, as no water is sprayed or dripped onto the foliage. It also helps to reduce water usage, making it an eco-friendly means for irrigation.
If propagated in the open-field, care should be taken to plant just after the frost period. Frost can burn the foliage. As the vegetable is specifically grown for its leaves, frost damage can severely affect the income potential of the crop. Warm and cool temperature varieties of seedlings can now be bought.
Storage After Harvesting
Harvesting is done by hand, mechanical means, or a combination. Once harvested, lettuce can be stored up to two weeks if stored in a facility where the relative humidity is 90% and the temperature remains between 1°C and 3°C. The vegetable can be stored for up to 30 days in special container conditions with optimal humidity, light, and temperature control. It still does not give the farmer much time to keep the produce fresh. Therefore, farming with the crop is best when close to the intended market and when the farmer has already secured an appropriate client or clients.
Farmers can purchase a variety of lettuce seedlings from Hishtil SA and have the plugs delivered to their farms. These plugs are disease and pest-free, while already protected for the first few days after transplant because the nursery applies a chemical treatment before shipment of the plant stock.