What to do if my tomato plant is turning yellow

Tomato plants are some of the most rewarding plants to grow in your garden, but occasionally they can give you a scare by turning yellow. This can signify a variety of issues, such as nutrient deficiencies, pests, or disease. Here are some steps to take if you notice your tomato plant turning yellow:

Check for water stress

The first thing to do is check for water stress. Tomato plants need about 1-2 inches of water per week, depending on the weather. If your tomato plant is yellowing, it may be a sign that it's not getting enough water. Be sure to thoroughly water your tomato plants on a regular basis, especially during hot and dry weather.

Inspect for pests

Pests such as spider mites, aphids, and whiteflies can all cause tomato plants to turn yellow. Check the undersides of leaves, as well as the stems and fruit, for signs of pests. If you find any, pick them off or spray your plants with insecticidal soap.

Test the soil

If your tomato plant is turning yellow, it could be due to a nutrient deficiency. You can test the soil pH to see if it's too low or too high. If the pH is too low, you can add lime to raise it, and if it's too high, you can add sulfur to lower it. Nutrient deficiencies can also be an issue, so it's beneficial to regularly fertilize your tomato plants with a balanced fertilizer.

Prune your plants

Overgrowth can also cause a tomato plant to turn yellow. Prune away any lower leaves or branches that have become diseased or are showing signs of yellowing. This will allow air to flow better around the plant and prevent fungal issues from forming.

Check for disease

If you've ruled out pest issues and nutrient deficiencies, then your tomato plant may be suffering from a disease. Tomato plants can be affected by a range of diseases such as early blight, septoria leaf spot, and fusarium wilt. Look for yellowing leaves along with other symptoms such as spots or wilting. If you suspect a disease, remove any infected plants immediately to prevent the spread.

Overall, if your tomato plant is turning yellow, it's important to diagnose the issue to prevent further damage. By taking the steps above, you can help your plants stay healthy and produce a bountiful harvest.