Planting Time for Tomato
Tomatoes are generally suitable for planting in spring (January to March) or autumn (July to August).
Seed Treatment
Soak the seeds in 55°C warm water for about 15 minutes, maintaining the water temperature. After disinfection, soak the seeds for another 6-8 hours, then take them out, wash them clean, and place them in a 25°C environment to germinate.
Sowing and Seedling Cultivation
Use a warm bed or a cold bed for seedling cultivation. Use 25-50 grams of seeds per mu (about 0.067 hectares). After sowing, cover with an arch shed. When sowing, mix the seeds with wood ash and spread them evenly in the seedbed. Cover with about 2 cm of finely sifted soil and water thoroughly.
Water and Fertilizer Management
Tomatoes need sufficient water for growth. Water frequently to keep the soil moist. Additionally, apply fertilizer twice during the growth period. Use mainly nitrogen fertilizer during the seedling stage, and switch to phosphorus and potassium fertilizers during the flowering and fruiting stages.
Pruning
Tomatoes have vigorous growth, with each node on the stem producing axillary buds, each of which can develop into a branch. If left to grow freely, it will lead to a dense canopy of leaves and consume a large amount of nutrients. Therefore, during the growth of tomatoes, continuously prune, pinch off suckers, and thin the leaves to regulate growth.
Copper Fungicide in Stores
Many stores offer copper fungicides, though brand names may differ, such as Copper Spray or Copper Dust. When purchasing, check the ingredients for the amount of MCE (metallic copper equivalent); the more it contains, the more effective it is. It’s best to spray when the tomato plants are young (within 2 to 4 weeks after planting) to prevent disease. Usually, spraying once, or at most twice (with a 7-10 day interval), is sufficient. Since tomatoes are prone to blight, which can be either early blight or late blight, spraying every two weeks thereafter can help ensure they remain disease-free.
Fertilizer
Tomatoes require a lot of fertilizer, especially calcium. Severe calcium deficiency can make it difficult for fruits to form, and even if they do form, they may turn black and rot from the base. Some people plant Tums (a medication for stomach pain that contains high calcium) next to their tomato plants because it dissolves easily in water. Others grind dried eggshells or shrimp shells and mix them into the soil. Many also use lime for supplementation. Garden stores sell packaged Garden Lime (or Agricultural Lime, which is powdered limestone) as a supplementary fertilizer, which is beneficial for tomatoes, eggplants, and peppers. Follow the instructions for the amount to use, as excessive lime can raise soil alkalinity too high.
Some people also bury banana peels next to tomato or rose plants, as bananas are high in potassium, which is beneficial for plants.
Common Tomato Questions
A frequently asked question about tomatoes is why they produce many flowers but no fruit. Besides calcium deficiency, another possible reason is the lack of bee pollination. If this is the case, you must pollinate manually. Use a cheap watercolor brush or a small brush to gently transfer pollen between flowers. This will facilitate the exchange of pollen between male and female flowers, leading to fruit formation (ensure the brush is clean and not reused).
To control fruit quantity and ensure larger, sweeter tomatoes, you can remove some flowers. This technique is also applicable to controlling the quantity of fruits in cucurbits.
Soil Moisture and Mulching
To maintain soil moisture, use mulch by covering the soil surface. You can buy mulch or use materials like pine needles, bark chips, or general compost. Apply mulch after watering.
Tomatoes require regular watering. If the roots lack water, flowers may wilt and fall off. If water is insufficient after fruit formation, the fruit may be tasteless (lacking sugar), and in severe cases, the fruit may drop.
Causes of Fruit and Flower Drop
Possible causes for tomatoes dropping fruit or flowers include:
- Sudden temperature changes (large day-night temperature differences)
- Insufficient or excessive humidity
- Excessive or insufficient nitrogen fertilizer
- Lack of bee pollination
- Water deficiency
- Pests and diseases
- Excessive fruit load
If your tomatoes suddenly stop bearing fruit in one year, it might mean that the soil has become diseased, and you may need to stop planting tomatoes or related plants like potatoes and eggplants in that location.
Tomato Blight (Early/Late Blight)
The most common diseases in tomatoes are early blight and late blight. These diseases cause leaves to develop yellow spots, resembling rust, and then wither, often spreading rapidly. To prevent blight:
- Inspect tomato seedlings for healthy leaves when purchasing, and choose Wilt Resistant varieties indicated by letters F, V, or N in the variety name.
- Plant different varieties with varying maturity times; earlier varieties are more susceptible to early blight.
- Rotate crops to avoid planting the same type of plant in the same location each year.
- Ensure adequate spacing between plants for air circulation, prune side shoots to improve air flow.
- Remove bottom leaves to avoid contact with soil-borne pathogens.
- Water the soil directly, avoiding leaves, and water in the morning to prevent prolonged leaf wetness.
- Support plants with stakes to enhance air circulation and reduce leaf contact.
- Clean up thoroughly after harvest to remove remaining leaves.
- Wash hands after handling diseased leaves to prevent spreading.
- Regularly inspect leaves and stems, removing and treating infected leaves promptly.
- Use copper or sulfur-based sprays to treat early/late blight, applying them on cloudy days or in the morning to avoid leaf burn in hot midday sun.
Other Tomato Issues
Tomatoes can also suffer from powdery mildew, rust, black spot, and anthracnose. Copper sprays are effective against these diseases. Spray leaves thoroughly, avoiding stems and young buds.
Even after using copper sprays on fruiting plants, the fruit is safe to eat after thorough washing, as copper products are tested and proven safe by health authorities. When spraying, protect yourself by wearing long sleeves and avoid spraying in windy, rainy, or hot midday conditions.
Aphids
Tomatoes can be infested by tiny green or white aphids, often found on young shoots. To control aphids, make a spray with liquid soap and vegetable oil (Canola oil), which will suffocate the aphids. Use one liter of water, one tablespoon of oil, and a few drops of soap.
Reapply all sprays if it rains within a day of application.
Growing Tomatoes
Tomatoes thrive in heat and full sunlight. Never expose them to frost. To warm the soil before planting, use mulch film to capture sunlight. Avoid using cold water for irrigation; warm water is preferred.
After fruit set, removing some leaves to expose the fruit to sunlight can help them grow larger and ripen faster. Additionally, prune the bottom one-foot leaves of young plants (about three feet tall) to prevent disease.
Tomatoes can be planted deep, unlike most plants, as they can form roots along the stem, leading to a healthier plant with more nutrient absorption.