How to Grow Bigger, Firmer Tomatoes

Tomatoes are one of the trickiest and unpredictable crops to farm, whether as a subsistence farmer cultivating a small garden or a commercial farmer working on a large expanse of land with more resources.

Its success depends on many factors. From the soil requirement to water and sunlight, every nutrient and growth-determining variable needs to be at the optimal point to bring about a bountiful harvest. 

Throughout its farming cycle, the tomato requires consistent care regarding sunlight, water, and soil nutrient management, along with protection from pests and diseases. If any of these factors is lacking, there will be an almost immediate consequence, one of which presents as the small and soft tomato fruits. In this article, you will learn four reasons why you have small and soft tomatoes and what you should do the correct the issue.

Causes of small and soft tomatoes

Nutrient Imbalance Just like humans, crops, especially tomatoes, also need a balanced diet, or balanced nutrients. Too many or too few nutrients will lead to growth issues in tomato crops. Nitrogen (N) is crucial for leaf growth, Potassium (K) is vital for water and sugar transport in plants, and Calcium (Ca) helps strengthen fruit cell walls. Excess or inadequate provision of all these nutrients will affect plant growth, fruit size, and general outlook.  

 Excess nitrogen during fruiting causes plants to focus on leaves, resulting in small, underdeveloped tomatoes. A deficiency in Potassium leads to small, soft, and poorly coloured fruits. And a lack of calcium causes blossom-end rot, the dark, leathery spot at the fruit’s bottom, and generally softer fruits

Improper Watering 

Water is critical to photosynthesis, which is the living formula for plants. However, for plants like tomato, water must be provided in an optimal quantity to ensure the best result. Overwatering or inconsistent watering is another reason why farmers can have small and soft tomato fruits.

When tomato plants are waterlogged due to overwatering, their roots can't breathe, leading to poor nutrient uptake, which would result in soft fruits. Excess water can also dilute the sugars in the fruit, making them less firm and flavorful.

Inconsistent watering can also interfere with nutrient absorption and lead to problems like fruit cracking and blossom-end rot, contributing to softness.

Heat Stress

While tomatoes love sunshine, extreme heat can be detrimental. When temperatures consistently soar above 32°C (90°F), especially during the night, the plant's metabolism goes into overdrive just to survive. 

This stress can interfere with pollination and fruit development, leading to smaller and sometimes misshapen fruits. Although climate conditions usually cause this, sometimes improper planting and spacing strategies can make this even more problematic for the crops.

Poor Pollination

For a tomato flower to develop into a fruit, it needs to be pollinated. Most tomato varieties are self-pollinating, meaning they can pollinate themselves with the help of wind or vibrations. 

However, if the conditions aren't right (e.g., very high humidity, stagnant air in a greenhouse), pollination can be poor. Incomplete pollination can result in small, oddly shaped fruits or no fruit at all.

How to prevent small and soft tomatoes on your farm

Here’s a practical guide to preventing the causes of small and soft tomatoes in your farm.

Preventing Nutrient Imbalance

Before you even plant, get your soil tested. This will tell you the existing nutrient levels and pH. The ideal pH for tomatoes is between 6.0 and 6.8.

Use a fertiliser that is lower in nitrogen and higher in potassium and phosphorus (P), especially once the plants start to flower. Look for N-P-K ratios like 5-10-10 or 10-20-20.

Incorporate a source of calcium into your soil before planting. Crushed eggshells, bone meal, or agricultural lime can be effective.

Preventing improper watering

Aim to keep the soil consistently moist but not waterlogged. A good rule of thumb is to water deeply when the top inch of soil feels dry.

Apply a layer of organic mulch (like straw, dried leaves, or grass clippings) around the base of your plants. This helps to retain soil moisture, regulate soil temperature, and suppress weeds.

If feasible, drip irrigation is an excellent way to deliver water directly to the roots slowly and consistently.

Preventing heat stress

During periods of intense heat, provide some shade for your plants, especially during the hottest part of the day. This can be achieved with shade cloths or by planting taller crops nearby to cast a shadow.

Ensure your plants are well-spaced to allow for good air circulation, which helps to cool them down.

Preventing poor pollination

On calm days, you can gently shake your tomato plants or the stakes they are tied to. This mimics the effect of wind and helps to release pollen.

While tomatoes can self-pollinate, attracting bees and other insects can improve pollination rates. Plant flowering herbs or flowers near your tomato patch.

Here’s a practical guide to correct small and soft tomatoes in your farm.

Correcting Nutrient Imbalance

If you suspect high nitrogen, stop using nitrogen-rich fertilisers and switch to a potassium-focused one (like sulphate of potash).

For a quick fix for calcium deficiency, you can use a calcium nitrate or calcium chloride foliar spray. Apply it directly to the leaves, preferably in the cool of the morning or evening, to avoid leaf burn. Be sure to follow the product's instructions carefully.

Correcting improper watering

If your fruits are soft, re-evaluate your watering practices. If you've been overwatering, allow the soil to dry out a bit more between waterings. If you've been inconsistent, establish a regular schedule.

Correcting heat stress

If a heatwave is forecasted, proactively apply shade covers. Ensure your plants are well-watered going into a period of extreme heat.

Correcting poor pollination

While tomatoes can self-pollinate, attracting bees and other insects can improve pollination rates. Plant flowering herbs or flowers near your tomato patch.

By paying close attention to these key areas, you can significantly improve the size and firmness of your tomato fruits. Remember, farming is a continuous learning process. Observe your plants, understand their needs, and don't be afraid to make adjustments. Happy farming, and may your harvest be bountiful and firm!