Pests
Weevils (vine weevils)
Night-feeding beetles that cut semicircular notches in leaves.
Adult weevils, including vine weevils, feed at night, chewing leaf edges and leaving distinctive semicircular notches. Their larvae live in the potting mix and attack the roots, which can make the plant wilt. In a heavy infestation, the combined damage to leaves from adults and roots from larvae weakens the plant, slows its growth, and can cause it to decline and die.
Signs to check
- Clean, semicircular notches, or scallops, along leaf edges.
- Damage that appears at night, with no culprit visible on the foliage during the day.
- Small black or brown beetles (7-12 mm, 0.28-0.47 in) may hide at the base of the plant or under the pot.
- If the plant wilts, white, C-shaped larvae may be present in the potting mix around the roots.
What you may notice
- Scalloped leaf edges · Regular, clean semicircular cuts along the leaf edge look as though they were punched out.
- Clean-edged holes in leaves · Round or oval holes with clean edges appear in the leaf blade, without discoloration around them.
What to do now
Install an insect barrier
- Choose fine-mesh insect netting. A mesh size of 0.8 mm x 0.8 mm (0.031 in x 0.031 in) is effective against most weevils and larger flea beetles. For the smallest flea beetles, choose 0.4 mm x 0.6 mm (0.016 in x 0.024 in) mesh.
- Cut a piece large enough to wrap the whole plant and its pot, leaving 15-20 cm (6-8 in) extra for fastening.
- Drape the netting gently over the plant. Keep it from pressing tightly against the leaves so air can circulate.
- Gather the extra fabric around the base of the pot, below the rim.
- Fasten the netting securely with string or a large rubber band. Make sure there are no gaps where an insect could crawl in from underneath.
- Check the netting every week for tears or openings.
Prevention
- Inspect every new plant carefully, especially under the leaves and on the surface of the potting mix.
- Always quarantine new plants for 2 to 3 weeks, away from other plants.
- Remove dead leaves and debris from the pot surface, where adults can shelter.