Back to basics: Growing tomatoes

Make sure of the ideal sowing time for seeds
Farmers should remember that when the basics are done correctly from the start, plants will grow optimally and deliver better yields and sales.
Ellanie Smit
Tomatoes are among the most popular crops cultivated, but maximising their potential requires farmers to understand the basics of growing them successfully and profitably.
According to Agribank’s Technical Advisor for Crops and Poultry, Hanks Saisai, various types of cultivars can be produced. There are fresh market varieties that a farmer can grow for household use or food establishments like restaurants, and then there are cultivars that are best suited for processing or canning purposes, and those used in dishes and beverages such as cherry tomatoes.
“To this end, it is important to consider the type of tomato required by your target market before you venture into production.”
According to Saisai, another essential point to note is the ideal sowing time for tomato seeds, which is usually around mid-August while transplanting can be done early in September.
“At the sowing stage, it is vital to sow tomato seeds in seed trays, at a depth of 1 cm. Once the seedlings begin growing, prepare the garden soil where the tomatoes will be grown until they reach maturity.”
He added that the prepared soil should be irrigated daily
“After three weeks, the seedlings in the trays can be transplanted into the garden which is best done in the evening to avoid heat stress.”
Saisai said that when transplanting, it is essential to follow spacing recommendations of 40 cm between rows and 30 cm within rows when growing indeterminate varieties. On the other hand, determinate tomatoes can be grown at spacing recommendations of 70 cm to 140 cm between rows and 40 cm within rows.

Watering
Saisai said that once transplanting is done, the young plants need about 500 mm throughout a 90 to 120-day growing cycle. “Essentially, farmers must develop a fixed irrigation programme as uneven irrigation may cause fruit cankering (cracking).”
He said that during the growing period, one should understand the beneficial effect of fertilizer application for the successful growth of tomatoes.
“During the first three weeks after transplanting, applying Nitrogen and Phosphorus-based fertilizers to stimulate foliage growth and to establish a robust root system, is essential. This can be maintained until the tomatoes start flowering, then Potassium-based fertilizers to ensure fruit quality should be applied.”
He added that the plants must be pruned to ensure that only the vines with flowers are left to concentrate the supply of Potassium to fruit development.
“At flowering, offer support to the tomato plants by staking. This is done by securing the plant with a stick to ensure it remains upright when bearing fruit.”
Saisai said that to keep pests and fungal diseases at bay, a spraying and dusting plan should be implemented. “Moreover, farmers are encouraged to scout for pests and diseases daily to swiftly respond to outbreaks.”
After growing tomatoes, it is advisable to plant a different crop to minimise the overutilisation of nutrients.
“Lastly, always remember that when the basics are done correctly from the start, it enables the plants to grow optimally and to deliver good yields, sales and a sustainable income.”