Sweet 100 Tomato Leaves Turning Yellow (Solved)

Are you worried about sweet 100 tomato leaves turning yellow?

Here is why the leaves turn yellow and how to prevent it.

Why are the Sweet 100 Tomato Leaves Turning Yellow?

Sweet 100 tomato leaves can turn yellow because of several reasons. It might be due to lack of sunlight or water availability, nutrient deficiency or too much acidic content in the soil, fungal, viral, or pest attack, or it might be transplant shock.

Here is how you can identify why your sweet 100 tomato leaves are turning yellow.

Watering Problems

Firstly, question yourself, “how are you watering the plant?â€. Too much or too little water can result in yellow leaves.

Your plant’s water needs can vary depending on your garden’s external environment and soil conditions. But you should adequately soak the plants in water at least once every five days.

Though soaking the plant is important, ensure the soil doesn’t remain wet for an extended period, as it might also result in yellow leaves.

The best time to water tomato plants is early in the morning. The right way to water tomato plants is to direct water near the base of the plant and avoid directly watering the leaves of the plant.

Lack of Nutrients

Leaves can also turn yellow because of the lack of nutrients. If the leaves are turning yellow because of nutrient deficiency, the most affected ones are that area to the base of the plant.

Potassium, magnesium, and nitrogen are three critical nutrients that can turn tomato leaves yellow.

If the entire leaves at the base of the plant are turning yellow, it is probably because of the lack of nitrogen. One of the best ways to combat nitrogen deficiency is to use fertilizer. Jobe’s Organics fertilizer (buy it here) is a great choice for ensuring appropriate nutrient availability to tomato plants.

However, make sure you use a moderate amount of fertilizer, as excess would promote foliage growth by compromising the yield.

The leaves affected by the lack of potassium usually give a visual effect of being burnt. You can spot the change in color on the outer edges of these leaves. Maintaining the potassium levels in the soil can help eliminate this reason.

Tomato leaves also turn yellow because of the lack of magnesium. Magnesium deficiency causes leaves to turn yellow and the veins to become prominent. Once you have identified magnesium deficiency, you can get rid of it with the help of Epsom salt.

Besides these major nutrients, iron and calcium deficiency can also cause discoloration of tomato leaves. However, they usually affect younger plants.

Lack of Exposure to Sunlight

Tomato plants need at least 6 to 8 hours of exposure to sunlight. Due to any reason, if the exposure to sunlight is limited, it might cause the leaves to turn yellow.

The most commonly affected parts of the plant in this scenario are the leaves near the base of the plant that don’t receive enough sunlight.

The best way of ensuring proper sunlight is thoughtfully selecting the location for planting. Make sure you choose a sunny spot.

However, if you have already planted tomatoes and suspect a lack of exposure to sunlight, try removing weeds and other plants in the vicinity of tomato plants.

Related: Tomatoes in Pots: 14 Important Answers You Have to Know!

Soil Compaction or Acidic Soil

Tomato leaves might turn yellow because of soil issues. Here, you need to ask yourself a few questions. Is the soil acidic? Have you measured the pH of the soil before planting tomatoes? Is it appropriate for growing tomatoes?

Tomato plants can only absorb nutrients from the soil if the pH is not maintained. Too much acidic soil can lead to yellow leaves and even no fruit production. The best way to avoid this situation is to do a soil pH test prior to planting tomatoes and treating the soil accordingly.

Does your garden have compact soil? It’s a big NO for growing tomatoes. Tomato plants cannot absorb nutrients from compact soil because it hinders root propagation.

Don’t worry if you have compact soil in the available location. A little digging can help you aerate the soil. However, make sure you don’t go harsh on the neighboring plants.

Pest Attacks

Though controlling pests is not a problem, identifying them as a cause of yellow leaves might be challenging. You have to look carefully along the stem of the plant to find traces of pests.

The common pests that feed on tomato plants are mealybugs and aphids. Predators such as ladybugs can help you get rid of aphids. Besides, you can use soapy sprays for mealybugs or hornworms. If you want to know how to easily kill pests with soapy water, go to this article.

Fungal Diseases

The primary symptom of a common fungal disease of tomatoes, Septoria Leaf Spot, is yellow leaves. It usually affects plants that have extended interaction with humid environments.

You can identify it by looking for circular spots that might look brownish-gray. These spots might be attached to the yellow regions of leaves. You should immediately remove the affected leaves once you identify Septoria Leaf Spot.

Tomato leaves can also turn yellow because of Fusarium Wilt. It attacks through the root system, and the water-absorbing capacity of the plant is severely affected.

You can identify it by its development cycle. Firstly, the leaves will turn yellow, the plant will wilt, and ultimately, the leaves will fall off.

Though you cannot revive a plant affected by Fusarium Wilt, you can prevent it by maintaining the pH of the soil.

Transplant Shock

The leaves might be turning yellow because they are trying to adjust to the new environment.

If you have transplanted the plant recently, yellow leaves are natural. Also, there is nothing to worry about or find a remedy for, as it will get better once the plant has adjusted to the new environment.

Related: Super Sweet 100 vs. Sungold Tomato (Comparison)

Maybe it’s Time to Say Goodbye

Maybe you haven’t noticed that it’s the end of the season. As the weather gets colder, the time to say goodbye to tomato plants comes nearer, and the leaves start turning yellow.

You can fasten their growth by removing yellow leaves and new blossoms if there are still unripe tomatoes on the plant. This way, the ripening fruits will access more nutrients and water. Resultantly, their growth will be accelerated.

Can Yellow Leaves Change the Taste of Your Tomatoes?

It depends on two factors. First, the cause of yellow leaves, and second, the extent to which the cause is spread. If the leaves are turning yellow because of watering or sun problems, it won’t change the taste of your tomatoes. All you have to do is remove the yellow leaves and work on removing the cause.

However, you must be careful if the plant is affected by a disease or if leaves are turning yellow due to a pest attack. Examine how much the disease/attack is spread. If it’s still limited to the lower leaves, you can remove the leaves, and the tomatoes won’t be affected.

In the case of Fusarium Wilt, the whole plant becomes useless. You cannot use the fruit of the affected plant. So, it’s best to discard the plant.

How to Revive the Sweet 100 Tomato Leaves?

The first step of reviving sweet 100 tomato leaves is identifying the cause of yellowing. In most cases, the yellowing is reversible or curable. So, you can revive the plant by following a certain procedure.

If the leaves turn yellow because of water problems, adjusting water availability will solve the problem. Maintaining the nutrients in the soil will revive the plants affected by nutrient deficiency.

As for the vase of diseases and pest attacks, you can use predators, sprays, and specific procedures to revive the plant.

However, there is one case in which you cannot revive the sweet 100 tomato plant, Fusarium Wilt.

How Much Time Does it Take to Revive the Sweet 100 Tomato Leaves?

It depends on the cause behind the leaves turning yellow and your efforts to revive them. If the leaves turn yellow because of water or sun problems, eliminating the cause can immediately revive the sweet 100 tomato leaves.

However, if the cause of yellowing is related to soil and you are using fertilizers or Epsom salt to revive the plant, it might take some time. Because adjusting nutrient concentration in the soil and absorbing these nutrients by the plant needs time.

How to Properly Take Care of Your Sweet 100 Tomato and Prevent Yellow Leaves?

Instead of finding remedies for reviving your sweet 100 tomato leaves, you can avoid this situation by taking care of your plants from the start. Here is how to prevent yellow leaves.

  • Before planting tomato plants, select the location thoughtfully. Make sure your plants will get 6 to 8 hours of sunlight.
  • Watering the plant is not enough. You should learn the right strategy to water tomato plants. Water the plants at the base and not directly over the leaves and flowers.
  • Keep a check on the soil. Aerate it before planting tomatoes. Also, check the pH level and make sure it’s appropriate for growing tomatoes. If your soil is acidic, you can raise its pH by using Jobe’s Additive De-Acidifier (buy it here).
  • If you use fertilizers for tomato plants, ensure you don’t exceed the amount. Too much fertilizer can affect the plant negatively.

Tip: If the leaves are turning yellow because of some infection, remove the leaves and discard them away from other plants. Do not use these leaves in compost. Wear gloves while discarding infected leaves and if you use any gardening device, make sure to sterilize it afterward.

I hope you can now identify the reason behind your sweet 100 tomato leaves turning yellow. It’s better to opt for preventions rather than look for remedies afterward. So, make sure you are fully prepared before planting tomatoes.


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