greenhouses I shade net I hydroponics I aquaponics
Pruning & trellising of tomato plants
to optimise greenhouse production
Shaping tomato plants can be done by pruning and trellising plants with indeterminate growth habit. This will enhance air circulation and ventilation, optimize space and sunlight, improve growth balance between roots, leaves and fruit, and optimize the working space. Advantages of shaping the tomato plant 1. Reduces the incidence of physiological disorders e.g. fruit cracking and the uneven ripening of fruit due to exposure to high solar radiation and high temperature 2. Reduces the incidence of fruit rot and soil-borne diseases 3. Maximizes the efficiency of photosynthesis 4. The upright plants have fewer disease problems with leaf spots and fruit rots because their leaves stay drier and are not in contact with pathogen laden soil. Disadvantages of shaping the tomato plant 1. Requires expertise (good management and skilled workers) 2. Trellising and pruning need to be done regularly – labour intensive 3. Plants can be damaged during training and harvesting. Pruning is simply the removal of the side shoots or suckers which develop between the main stem and the leaf. It helps to maintain a balance between
vegetative and reproductive growth. Generally, if you do not prune or prune few side shoots, your plant will show excessive vegetative growth which may result in smaller fruit size. Care should be taken not to prune the growing point of the main stem otherwise your plant will stop growing and bearing fruit. Suckers can be removed with thumb
and forefinger by pulling outwards. They are removed while they are young and succulent (2 to 5 cm long) when they heal faster. Large suckers are not easily removed and can create a larger wound, which takes time to heal and can be an entry point for pathogens. Experimental evidence has shown that there is a high reduction in 10
Growing-point
Sucker/ side-shoot
Side-shoots
The removal of sucker/side-shoots with the thumb and forefinger – sanitizing hands is a must in any greenhouse to ensure disease control.
Undercover farming I
July/August2020
I Volume 17 No 4 9
