Cutworms
Cutworms are moth caterpillars that live in the soil and feed at night, chewing through young stems at the base. One caterpillar can topple a row of transplants.
Pests
What it looks like
The plant is cut, not eaten.
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Felled seedlings Stems severed at soil level, the top lying beside. -
Grazed stems Bark chewed around the stem base. -
C-shaped caterpillars Grey, brown or green caterpillars curled in the soil. -
Damage in lines Several plants in a row lost night by night.
How to confirm it
Dig around the stump.
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Search the soil
Look 2 to 5 cm (1 to 2 in) deep around the damaged plant.
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Night check
They feed at the surface after dark.
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Recent turf
Common in beds made from lawn or rough grass.
What to do
Find them and protect stems.
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Dig them out
Search around damaged plants each morning.
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Collars
Put a collar of card or a cut-down bottle around each transplant stem.
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Keep weeds down
Weeds give moths places to lay eggs.
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Nematodes
Water on nematodes in warm, moist soil.
Prevent it next time
- Cultivate beds before planting to expose caterpillars to birds.
- Plant out sturdy transplants rather than tiny seedlings.
- Keep weeds down in late summer.
What not to do
Do not resow the same spot without searching the soil first; the caterpillar is still there.
In the growing guides
Where the guides mention it, with plant-specific advice.
Sources
- Cutworms, Royal Horticultural Society