What to Do If Tomatoes Won't Grow Big? Cause Analysis and Solutions

Tomatoes are widely grown, and various problems arise during cultivation that can affect tomato yield and quality. Many vegetable growers report that their tomatoes won't grow big and can't find a solution. So what should be done when tomatoes won't grow big? Let's take a look together.

1. Reasons Why Tomatoes Won't Grow Big

1. Variety

With some varieties, the size difference between trusses is small, and some varieties are suitable for long-term harvesting, able to set fruit up to 17-20 trusses, but this type of seed is relatively expensive. With ordinary varieties, each truss is smaller than the previous one, and the fruits toward the top are smaller. These fruits are more suitable for cultivation with a short harvest period, generally setting 3-4 trusses, after which the growing tip is pinched off, leaving 3-4 fruits per truss.

2. Fertilizer

When plants lack various growth elements, the fruits will become smaller. A deficiency of magnesium, manganese, and boron will also affect fruit size. In addition, improper fertilization can also affect fruit size. For example, applying diammonium phosphate too much and too frequently causes phosphorus toxicity, and the fruits will also become smaller; applying potassium fertilizer all at once can also cause a reduction in yield; if there is too much boron fertilizer in the greenhouse, it will also make the fruits smaller.

3. Cultivation

Improper cultivation management can also cause tomatoes to not grow big, for example, not setting up trellises, causing the plants to lodge; another is soil drought and lack of water, so the fruits cannot expand normally; there is also growth hormone toxicity, which is the most common cause of smaller fruits in greenhouses, mainly due to flower dipping. Each time a layer of flowers is dipped, the growth hormone accumulates a little, and after three or four trusses the fruits are affected, so every 3-4 trusses, gibberellin is used once to correct it.

2. Solutions

From transplanting in the greenhouse to before flowering, plant growth is small and the demand for nitrogen fertilizer is low. The nitrogen fertilizer in the base fertilizer can fully meet plant growth, so there is no need for nitrogen fertilizer at this stage. Entering the flowering and fruiting stage, as the temperature rises, growth speeds up and growth volume increases, so nitrogen fertilizer needs to be applied in time to ensure nutrient supply. Starting from the first truss flowering, 20-25 kg of nitrogen fertilizer can be applied per mu as a top dressing, combined with potassium fertilizer, to ensure normal tomato growth. Later, as the temperature gradually rises and evaporation increases, the interval between waterings gradually shortens, so the nitrogen fertilizer applied with each watering must not be too much, in order to reduce nitrogen loss with the water.

  The above is an introduction to what to do if tomatoes won't grow big. I hope it can help you. To learn more related knowledge, please follow us.