Control temperature and sunlight levels carefully to avoid extremes, using combinations of heating, ventilation, shade netting and white greenhouse paint as appropriate.
Choosing greenback-resistant cultivars will help avoid greenback and whitewall. Seed catalogues should list current greenback-resistant cultivars. Examples include ‘Alicante’, ‘Shirley’ and ‘Craigella’.
Avoid erratic watering and if plants with ripening fruit do become too dry, do not flood them, but bring the soil moisture level back up again gradually.
Feed tomatoes regularly to maintain high soil fertility. Special tomato fertilisers have high levels of potassium to encourage good fruit development. Adequate potassium nutrition is required to reduce greenback and whitewall, but excessive use of potassium-rich fertilisers can lead to magnesium deficiency and blossom end rot. Use of tomato feeds as directed by the manufacturer should avoid over or under supply of potassium.
Pesticides are not required to treat physiological problems as no pest or disease is involved. Therefore there is no chemical control.