However, the most common reason for tomato leaves turning purple is potassium deficiency.
Other nutrient problems, as well viral and pest infestations, may also cause this issue.
Read on to learn about these various causes, possible treatments, and means of prevention.
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Young tomatoes cannot absorb potassium as easily from cold soil as they can from warm soil.
As the soil warms, leaves might turn to their natural green.
Treatment
To remedy potassium deficiency, feed tomato plants with fertilizer that is high in potassium.
Look forfertilizers that specifically mention tomatoes.
Phosphorous Deficiency
Tomato plants may also struggle to absorb phosphorous from cool and wet soil.
Plants deficient in phosphorous may also experience stunted growth, necrotic spots on the leaves, and leaf cupping.
All these symptoms are more likely to arise on older leaves.
This issue can cause delayed blooming and delayed maturity.
Feed phosphorous deficient plants with a phosphorus-heavy fertilizer, such as bone meal.
In the event of tomato spotted wilt, remove and destroy the affected plants.
Insect Infestation
The purple you are seeing on your tomato plants may actually be purple insects.
Garden springtails, which are quite small and purple, prey on seedlings.
These insects have a forked appendage that they use to project themselves into the air instead of wings.
Fortunately, this isn’t a death sentence for your tomato plants.
To minimize this problem, always plant tomatoes in well-draining soil and provide good air circulation.
you’ve got the option to sprinkle diatomaceous earth around the plants to kill springtails.
Many tomato cultivars are resistant to various diseases.
Two cultivars that withstand tomato spotted wilt well are ‘Top Gun’ and ‘Mountain Majesty.’
Tomato plants that have been overwatered will droop.
Both their stems and foliage will appear saggy and limp.
Tomato Leaves Rolling?.
Recognizing Tomato Problems.Colorado State University Extension.
Connecticut Agricultural Experiment Station.
