Weeds compete with the tomato plants for light, water and nutrients. Sometimes they provide shelter for organisms that cause tomato diseases, such as Tomato Yellow Leaf Curl Virus (TYLCV), and reduce the yield. Effective non-chemical weed management begins with deep plugging, diverse crop rotations and competitive cover crops.
The following integrated practices are useful for controlling weeds effectively:
- Remove the previous crop residues and use sanitation practices to avoid introducing weed seeds.
- Deep cultivation and exposing soil to sunlight before transplanting help to destroy the weed seeds.
- It is important to keep the field weed free for 4-5 weeks after transplanting. It is during this period that weed competition must be suppressed to avoid reduction in yield.
- Weeds growing between crop rows are the easiest to control. Shallow plugging (up to a depth of 15-20 cm) or using mulch usually removes them.
- Hilling the soil towards the plant row (earthing-up) helps to smother small weeds in the row and tomato plants develop roots further up the stem.
- Mulching with plant residues is good for weed suppression, soil moisture retention and slow release of nutrients as they decompose.
Harvesting will continue for about one month, depending on climate, diseases and the cultivar planted.
Tomato can be classified in four stages of maturity:
Stage 1: Seed are white in color (immature) and can be cut when the tomato is sliced. There is no juice inside the tomato.
Stage 2: Seeds have a tan color (mature) and some juice present.
Stage 3: Seeds are pushed aside when cut. The colour inside is still green.
Stage 4: Juice becomes red in color.
Tomatoes that are harvested at the first stage of maturity will ripen into poor-quality tomatoes. Tomatoes harvested at third and fourth stages of maturity will ripen into good-quality tomatoes. It is also good to look carefully at how ripe the tomatoes are. How ripe a tomato is when it is harvested affects the fruit composition and tomato quality. Tomatoes accumulate acids, sugars and ascorbic acid when they ripen on the plant. Field-ripened tomatoes have a better flavour and overall quality than tomatoes that ripen after picking. Hence it is important to understand ripeness stages.
Tomatoes are picked in picking containers (nylon net bags or plastic buckets). These picking containers need to be emptied into larger containers which must not weigh more than 25 kg. The containers need to hold only tomatoes that are mature, ripe and free from damage. When the field containers are full, they should be transported to a sorting area located on the farm. In sorting areas, the fruits are washed and sorted by size, colour and variety. Sorting areas need to be out of direct sunlight, preferably cool and clean. Washing and sorting can be done with long water containers. It is also possible, to add a permissible amount of chlorine solution to the water, to disinfect the tomatoes. Once the tomatoes are taken out of the sorting canal they must be dried and carefully placed in a container, ready for dispatch to their final destination. Uniformity is one of the first attributes that buyers look for. Appearance comes before aroma and taste.
Badly packed tomatoes will not only ruin the tomato crop for sale, but will also mean lower prices. Even if tomatoes are just being sold at the farm gate, they will require some form of packaging, which can be a simple traditional basket. Packaging protects against pathogens, natural predators, loss of moisture, temperatures, crushing, deformation of tomatoes and bruising. It is a good idea to use padding material at the bottom of packages and in between layers of tomatoes.
Storing tomatoes in tropical and subtropical climates can be difficult without cold storage. Tomatoes that are to be sold fresh for table consumption must not be stored for long. Tomatoes are picked when ripe and stored for a few days in a cool room, after which they transported to distant markets. During the journey the tomatoes will ripen to the market stage. Tomatoes will deteriorate if they are kept at temperatures below 10°C for longer than 2 weeks or if kept at 5°C for longer than 6 to 8 days.