Why Are My Tomato Leaves Curling?
Tomato plants are a summer staple in many UK gardens, but when their leaves start to curl, it's easy to panic. Leaf curl can look alarming, but it often signals something your plant is trying to tell you. Here's how to diagnose the issue and help your tomatoes thrive again—organically.
Common Causes of Curling Tomato Leaves
1. Environmental Stress
Tomatoes are sensitive to sudden changes. Leaf curl can happen when:
Temperatures fluctuate wildly (especially in early summer)
The plant is over- or under-watered
Wind exposure dries out leaves
2. Nutrient Imbalances
Curling may also indicate a deficiency or excess:
Nitrogen overload causes bushy growth and leaf twist
Calcium deficiency can cause curling and blossom end rot
3. Pests
Sap-sucking insects like aphids, whiteflies, and thrips distort leaves and transmit diseases.
Look under leaves for signs
Sticky residue (honeydew) is a clue
4. Viral Infections
Curly Top Virus or Tomato Yellow Leaf Curl Virus can stunt growth. Unlike other issues, viral infections often show bright yellowing, stunted new growth, and twisted shapes.
Natural Solutions and Organic Treatments
1. Adjust Watering and Shade
Water deeply but less often to encourage strong roots
Use mulch to retain moisture and regulate temperature
Provide temporary shade if there's a heatwave
2. Boost Soil Health
Add compost or well-rotted manure in planting beds
Spray with Actiferm or EM (Effective Microorganisms) to improve soil biology. These are available from Agriton UK and help enhance microbial life and nutrient uptake.
3. Control Pests Organically
Spray with a diluted castile soap solution
Introduce beneficial insects like ladybirds
Use yellow sticky traps in greenhouses
4. Strengthen Plant Immunity
Apply seaweed feed or comfrey tea fortnightly
Rotate crops to reduce disease buildup
Enhance soil vitality with Agriton’s natural potassium-enriching products to support flowering and fruiting (check agriton.co.uk for the latest range)
When to Worry
If your tomato plant shows severe yellowing, slow growth, and brittle curling, it might be a virus. Sadly, there’s no cure. Remove infected plants and don't compost them.
Final Tips
Tomato leaf curl is a symptom, not a sentence. With the right care and a bit of observation, most tomato plants bounce back beautifully. Keep it organic, stay consistent, and your tomatoes will reward you all summer long.
Need help with tomato issues? Explore our gardening solutions and learn how Actiferm and EM from Agriton UK can support stronger, more resilient plants—naturally.
