Glossy, stiff, curled growing tips that stop growing
Newest leaves become glossy, leathery and downcurled, then bronze and stop expanding; can spread plant to plant..
- Also called
- shiny new growth
- glassy leaves at top
- tips look wet and shiny
- new growth stiff and curled
- broad mite damage
Likely causes, most likely first
Ranked for this sign on its own. Your stage, medium and readings change the order, so run the checker for your plant.
PossibleBroad mites
Fix: Confirm at 30-60x. Remove and bag heavily infested plants; mothers and clones are the usual source. Release predatory mites (e.g. Neoseiulus californicus or Amblyseius swirskii) on the rest, keep tools and clothes clean, quarantine new stock. In flower, removal is usually the only clean option.
Recovery: New growth expands normally (not glossy or twisted) within 10-14 days.
How to confirm it
- Magnifier check of leaf undersides and new growth. Use a 10-20x loupe for spider mites, thrips, aphids and whiteflies, and a 30-60x lens or clip-on phone macro for broad and russet mites. Check the undersides of 10 affected leaves across several plants and the newest shoot tips, in white light. Look for moving dots, eggs, shed skins, webbing, slender insects with black specks, and glassy specks on new growth.
- Watch new growth for 5-10 days after one change. Make one correction at a time, mark the top node with a twist tie and photograph the same leaves every 2-3 days. Damaged leaves never recover; judge only new growth and whether the symptom stops spreading. Mobile-nutrient symptoms stop climbing within 5-7 days; immobile ones show in new leaves within 7-10 days.
Look for
Shiny, hardened, downward-curled leaves and bronzed tips at the top of the plant; nothing visible to the eye..
The full guide: Broad mites on cannabis: life table, spread and control (plus russet mite summary)
Guidance, not a guarantee. The checker weighs common causes against what you tell it; confirm with the tests before you treat, change one thing at a time and watch the new growth.
