South Africa's tomato agriculture are focussed on areas like Limpopo, Mpumalanga, parts of Kwazulu-Natal and the Western Cape. Therefore, growing tomato in Johannesburg is going against the grain. This blog will guide you on how to make it work in Johannesburg.
Cultivar
Considering factors like temperature variations, heavy rainfall, and potential frost in Johannesburg, here are some tomato varieties that tend to perform better in Johannesburg than others:
Florodade: Known for its adaptability to warmer climates, Florodade is a determinate variety that produces medium to large-sized fruits. It's a popular choice due to its disease resistance and ability to thrive in fluctuating temperatures.
Fortress: This determinate variety is praised for its resilience against various diseases common in tomatoes. It bears medium-sized fruits and is suitable for Johannesburg's climate due to its adaptability to different weather conditions.
Karino: Karino is a versatile tomato cultivar suitable for Johannesburg's climate. It's known for its heat tolerance and produces round, red fruits that are resistant to cracking, making it an excellent choice for the local climate's temperature fluctuations.
Roma : Though generally suited to various climates, Roma, a determinate variety, can perform well in Johannesburg's conditions. It's ideal for processing or sauces due to its meaty texture and low seed content.
Other varieties can work, but be sure to check their adaptability first
Temperature
Tomato is a warm-season crop that is sensitive to frost.
An average daily mean of 20 ° to 24 °C is optimum for growth, yield and fruit quality.
Fruit set and quality are poor at temperatures below 12 °C and 35 °C.
Hot, dry winds cause excessive flower drop while continuous moist, rainy weather conditions result in the occurrence and spread of foliar diseases.
Season
Summer.
It's very common for a tomato plant to grow well in Winter, but then when it gets hit by frost, it dies. It looks like it was frost bitten.
Don't even bother with Winter unless you have a greenhouse.
Even Spring is risky because cold fronts still reach us in Johannesburg until October, and rainfall is sporadic
Sunlight Requirements
In the sunny climate of Johannesburg, sunlight conditions are perfect for tomatoes.
Aim for a minimum of 6 to 8 hours of direct sunlight daily to optimize their growth.
Tomatoes exposed to more sunlight tend to develop a deeper red color, which often indicates better taste and higher sugar content compared to tomatoes that receive less sunlight.
A more green or orange color is telling you it is not getting enough sun, and the tomato may be sour
Water Requirements
Although rainfall in the summer season in Johannesburg is enough, it is not regular, so you have to water it manually to provide consistency.
Even Moisture Levels: Aim for consistent moisture in the soil to avoid extremes of dryness or water logging. Irregular watering can lead to issues like blossom end rot or split fruits. That's why farmers nowadays are growing tomatoes with hydroponics.
During the first four weeks apply 21 mm of water per week,
During the following eight weeks apply 38 mm per week
Plants that are irrigated late in the season produce watery fruits of poor quality
Heavy irrigation after a long dry spell without prior light irrigation results in fruit cracking
During hotter periods, when evaporation rates are higher, you might need to water more frequently. Consider watering every 2-3 days, adjusting as needed based on soil moisture levels.
Soil Selection
Opt for well-drained sandy loams or deep loams enriched with organic matter.
Maintain a pH value between 6 to 7 for optimal growth.
Pest and Disease Management
If you damage a tomato plant, wrap it with a plaster to prevent disease
Spider mites are the most common pest for tomato. Sometimes they only come after the tomato plant is ending its life - not necessarily that it's the cause of death. Check for a range of symptoms to diagnose.
Implement preventive measures such as crop rotation and dispose of dead tomato plants in a compost heap- not lying around where tomato will be planted again
Avoid an overhead sprinkler irrigation system because wet leaves encourage early and late blight.
Fertilizing
Tomato is a heavy feeder of plant nutrients including nitrogen, phosphorus and potassium and it responds well to organic fertilisers
If you remember anything, remember this:
Consistency in watering is key
Tomatoes respond well to compost
Conclusion
Cultivating tomatoes in Johannesburg offers an exciting journey for gardening enthusiasts. Understanding the city's unique climate nuances and providing adequate sunlight and consistent watering are essential for a flourishing tomato garden. By optimizing growth conditions and choosing suitable cultivars, you can yield bountiful harvests of fresh, flavorful tomatoes for your enjoyment.
Comment on the post if you have any tips to share with others.
Information source: https://www.nda.agric.za/docs/Brochures/ProdGuideTomato.pdf