Plant problems · Nutrients · Any stage · Act this week
Nutrient burn
What you see
- Leaf tips turn yellow, then brown and crispy, a few millimetres in
- It starts on the tips of the leaves that get the most light and feed
- Burn creeps further along the edges if feeding stays strong
Why it happens
More salts reach the roots than the plant can use, from strong feeds, hot soil or salts building up in the pot.
What to do
- Lower the feed strength by a quarter to a half
- In coco and hydro, water with pH adjusted water to 20 percent runoff to wash out salts
- Burnt tips stay brown; watch that the burn stops spreading on new leaves
Next time
- Measure EC or PPM if you can and raise feed slowly
- Water to some runoff to keep salts down
Easy to confuse with
- Too much nitrogen (the claw): Leaves are very dark green, almost shiny
- Potassium deficiency: Leaf edges and tips turn yellow, then brown and crispy, starting on older leaves
- Light burn and light bleaching: The top leaves closest to the light turn yellow or white while their veins stay green
Not sure?
Take a photo of a leaf tip close up, and the whole plant from above and ask the Grow Doctor, or send it to the grow companion on Telegram.