how much sun do tomatoes need

How Much Sun do Tomatoes Need for a Bumper Harvest?

Ian Mutuli
Updated on
Ian Mutuli

Ian Mutuli

Founder and Managing Editor of Archute. He is also a graduate architect from The University of Nairobi, Kenya.
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A total of six hours of direct sunlight is how much sun exposure tomato plants need. However, there are different types of tomato plants, some of which will not do well in the afternoon sun or exposure to full sun all day long.

The kitchen garden has real estate that must be distributed strategically to get the best results. One must-have plant in your garden is the tomato, which is a delicate plant to grow. The tomato plant is sensitive to many elements, including direct sunlight. When growing tomatoes, you can control things like diseases, pests, and water. However, the sun is out of your control, and you can only be strategic about how you plant tomatoes.

How much sun do tomatoes need, and how do you know the tomato plants are overexposed to the sun? We are here to tell you all about it.

How to Plant Tomatoes in High Heat Regions/Season

a) Shade

You need to take advantage of the shade in every way possible. The growing season might be here, but you can not take your chances with the recent climate surprises. You need to look ahead in areas with warm temperatures to secure a successful harvest. Take advantage of container gardening benefits. You can provide shade for each tomato plant by creating a partial shade cloth or sun filter. Growing tomatoes in the shade are one thing. You still have to take care of the plants in other ways.

A full shade is not advised as the tomato plants need sunlight to a degree.

b) Enough Water

The worst thing for a tomato plant or indoor plants is inconsistent watering. If the tomato plants are in direct sunlight, you can not miss out on watering them because they compete with the full sun for the limited water. If you remain disciplined, you will get more plant fruit production.

When watering, avoid wetting the leaves. Wet leaves can lead to fungal diseases. To help the tomato plants retain water, you can learn how to mulch tomatoes.

c) Pay Attention

While it may be hard to know what is going on with the plants while they are still seedlings, you can tell if there is a problem once they are grown up. First, you need to know the different diseases that attack tomatoes. Next, you need to know the white spots on tomato leaves and their effects. Finally, yellowing leaves, spots on fruits, wilting, and what pests might attack tomatoes should be information you have at your fingertips.

How Sun Exposure Affects Tomato Plants

Planting tomatoes requires a lot of considerations, from how much spacing you will give them to how much water and heat they receive. The sun can affect tomato plants both directly and indirectly. Excessive heat and direct sunlight can hinder healthy growth, especially in hot regions. On the other hand, the sun will directly affect the production, and you might miss out on a good harvest. The ability of the tomato plants to produce fruit depends on sun exposure, and here are some ways you can tell the direct sunlight is hard on the tomato plants.

1) Sunscald

Gardening Tip: Ensure the tomato plants get the morning sunlight and not the midday sun to prevent sunscalding.

Sunscald occurs when the tomatoes are exposed to direct and intense sunlight. You can notice sunscald on the fruits that are still green or ripening. When you see white patches on the green or ripening fruit, there is a chance that the full sun exposure is having its effect. The sunscald will most likely be on the side of the fruit facing the sun. As the fruit keeps growing, the patch may start greying, forming a scar on the side of the tomato. A black mold is likely to form on the affected side.

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Solution: Provide Shade

While you can not move the plant to a shade at this stage, you can control the amount of sunlight hitting the tomato plants. Notice where the afternoon sunlight hits on the fruits and targets this area. The tomatoes still need the morning sunlight, which provides the much-needed sunlight without the intense heat. You can create a partial shade to take care of the fruits in the afternoon heat.

Solution: Avoid Pruning

There are more ways of protecting the tomatoes from scalding. You can avoid pruning the tomato plants to provide shade when there is too much sun. This can be easy to do when gardening does not occupy a large surface area. Tomatoes are pruned to provide support when there is too much weight. To compensate for this, you can provide a support for the tomato. This process is called caging.

When you notice scalding on the tomatoes, you can remove them and let them ripen in the house or on the window sill. If the sunscald has turned black, there could be mold, which is not safe to consume. You should know what black spots on tomatoes mean.

2) Decreased Production

Gardening Tip: Plant more heat-tolerant tomatoes to get a better harvest in the hot season.

There is an average number of tomatoes you expect to harvest on the total number of tomatoes planted. When tomatoes are exposed to the sun for eight or more hours, their production is hindered because the plant starts dropping flowers, and you will not see much fruit. The plant needs to conserve energy and will avoid making fruits.

Apart from fruit production, the humidity makes pollen sticky, making it impossible to pollinate the flowers.

3) Slowed Growth

Tomato plants are not sun-loving plants. When growing a tomato plant, ensure it is somewhere that will receive at least six hours of sun. Like any other plant, tomato plants require the sun but will cave to the harsh midday sunlight. At least eight hours of direct sun will mess up the tomato plants because that is more than enough sun.

Gardening Tip: If the tomato plants are not under harsh direct sunlight, you can use fertilizers to increase growth.

Another problem that comes with too much sun is rapid water. Tomato plants grow in areas with enough water and will wither at the slightest lack of water. You may have to water the tomato plants regularly to keep them alive. Irregular watering will reduce your harvest.

To grow tomatoes effectively, you may need to use fertilizers. However, when the heat is too much, you may want to limit your fertilizer. Fertilizers add nutrients and are essential. However, even if you have the best fertilizer to nourish tomato plants, lack of water may lead to blossom end rot on the growing tomatoes due to too much nitrogen. The right fertilizers are never a problem if there is enough soil moisture.

Final Take

Tomatoes are fun to plant, and the joy of seeing the first flowers is tremendous. However, the sun can be one of the biggest enemies to tomato plants. Sadly, tomato plants need the sun to survive and produce fruit. Therefore, you must find a balance to ensure you reap during the harvest season. You can plant heat-tolerant tomatoes to reduce the risks that come with a lot of sunlight.

Ian Mutuli

About the author

Ian Mutuli

Founder and Managing Editor of Archute. He is also a graduate architect from The University of Nairobi, Kenya.
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