How to grow tomatoes

The tomato is one of the seasonal moneymakers, that farmers should go for. There are mainly two seasons of tomatoes a year, however if one uses irrigation, tomatoes can be grown all year round.  

The amount of tomatoes grown in Uganda is not recorded, however the country supplies countries like Southern Sudan, Democratic Republic of Congo (DRC) and Rwanda.    

The most popular varieties of tomatoes at the moment are Assila, VL 642, Ranger F1, Rounder F1 and money maker. These are popular because they yield well and are resistant to wilts. These can be grown across most parts of the country, as long as the soils are loam, dark and fertile. The seeds are packed in various sizes, from sactchets of 25-50seeds which cost sh2,000-sh5,000, 100 seeds which cost sh12,000, 1,000 seeds which cost sh43,000 and more. An acre needs around 10,000 seedings which cost around sh385,000.

However, if you are not a commercial farmer, you can squeeze seeds from the tomatoes that you use at home, dry the seeds and then plant them.

The entire cost of maintaining an acre of tomatoes from planting to harvesting is around sh5m. This includes buying appropriate pesticides at around sh1m, two weedings at sh1m, watering the crops by laborers if you do not have irrigation at sh1m and harvesting the crop through 3months.  

Nursery bed preparation

Potting (putting seeds in pots) is ideal for producing vigorous seedlings from the nursery. Potting materials can be got from many agri-input stores at around sh20-50 each.

-Mix one wheelbarrow of soil to another of decomposed manure. Manure can be got from livestock farmers, for example chicken droppings or dung. At the moment, a 100kg bag costs between sh10,000-sh15,000. Alternatively, you can decompose your kitchen remains, for example left over foods, for three months in a covered pit to create manure.

- Mix 50g of DAP in one wheelbarrow of decomposed, fine manure in order to enhance root establishment. A 50kg bag of DAP costs sh130,000. You need two bags per acre. Fill the mixture in pots and put one seed per pot. Seed should be one inch deep.

-Arrange the pots in order and cover them with grass. Water every morning with each seedling taking at least 30mm.

-Remove the grass after a week or upon germination. You can remove it  by plucking it out using your hands.

-Spray the seedlings with a mixture of 1ml of cypermethrin and 5g of mancozeb with a  1litre sprayer.  It protects the seedlings from pests.

-Spraying is done once per week in order to protect the seedlings from fungal diseases and pests.

-Seedlings are ready for transplanting after three weeks.

Transplanting in the evening is ideal in order to avoid the hot temperatures of the afternoon because they may cause them to wither.

Main garden

-Spacing: 90cm by 90cm without staking 75cm by75cm with staking. Staking is when small poles are placed near the plants for them to grow upwards on.

-Create furrows in rows were the seedlings are to be transplanted

-Put manure in the furrows. It can be NPK, with a tea spoon in each hole.  

-Dig holes for the transplants and incorporate DAP in holes 5g per hole.

-Mix the blend with the soil in the hole. Put one seedling per hole

3days from transplanting drench the root zone of the seedlings with Fertiactyl GZ. (100mls of GZ in 20litres) 20litres cost sh150,000.  Make the second application of GZ a week after the first application and top dress with 10grams of NPK at 4 weeks from transplanting. Buy fertilizers and pesticides from only certified dealers to avoid fakes. 

-Make the second application after 2 weeks.

-If you have irrigation, water the crops at least three days a week, strictly in the mornings and evenings, in order to prevent water evaporation. 

Diseases of tomatoes

It is advisable to plant varieties like Assila have 100% resistance to tomato yellow leaf curl virus (ekigenge)

Common diseases are early and late blight (ekibabuko), Powderly and downy mildew, bacterial specks.

Control

Avoid the environment that favors fungal diseases I.e avoiding stagnant water on the leaves,  avoiding weeds in the garden they can become alternate hosts, remove diseased leaves that have fallen the ground.

-Conduct regular scouting in the garden to check for signs of disease.

-Do preventive sprays of preventive fungicides I.e. Mancozeb and copper based fungicides

-Preventive sprays should be done at least twice a week in a dry season and thrice in a wet season

Incase of manifestation of disease curative fungicides should be used e.g Ridomil, tatamaster or emexyl they all have the same active ingredient I.e mancozeb and metalaxyl. These can be got from certified dealers around the country.

Curative fungicides can prevent, cure eradicate diseases

70grams of preventive fungicides in 20 liters of water should be Ideal dosage for control of the disease,whereas for curative fungicides 50grams in 20 liters of water is ideal. Costs for these fertilizers ranges from sh15,000 on wards.

Pests

Common pests

Mites, thrips, aphids, whiteflies.  They are commonly sucking insects

They suck sap out of the leaves, causing leaves to lose the photosynthetic potential because of loss of the green colour.

-Some like thrips feed on the flowers causing flower abortions

They also feed on the fruits hence affecting the market quality of the fruits

Control

Regular scouting for pests is a must. Destroying alternative hosts like weeds from the field

Conducting insecticidal sprays. Recommended pesticides include Durban, larva,tarfgor, cypermethrin,  Rocket, Fenenvalate,Malataf. Costs start from sh15,000, depending on the quantity.

Note

Alternating these pesticides can be more effective in controlling the pests because sticking to one pesticide can bring about resistance of the pests to the insecticide

Rocket herbicide should be used more effectively before flowering because when used during the flowering stage,

Insecticides should always be used as indicated on the label.

Harvesting

Most tomatoes varieties are ready for harvest 75 days from transplanting. An acre can produce around 25tonnes of tomatoes. With a conservative price of sh1,000 per kilogram, that makes around sh25m. 

The harvest goes on for at least 3 months depending on how the farm was maintained.  Tomatoes are harvested by picking the mature/ripe fruits off the plant. They need to be stored in cool environments to increase shelf life.