Fertilizer and salt burn
Scorched leaf edges and a white crust when fertilizer and minerals build up in the pot.
What you'll see
- Brown, scorched leaf tips and edges, sometimes with yellowing.
- A white, crusty film on the soil, on the pot rim or on the outside of clay pots.
- Lower leaves drop, and the plant wilts or stops growing even when watered.
Why it happens
Extra fertilizer and minerals from hard water build up in the mix as water evaporates, and they pull water out of the roots.
How to fix it
- Scrape off any white crust from the soil and pot.
- Pour 2 to 3 times the pot's volume of plain water through the mix, and let it drain completely.
- Repot into fresh potting mix if the pot is small or badly salted.
Keep it from coming back
- Feed at the rate on the label or weaker, and far less in winter.
- Flush pots with plain water every 4 to 6 months.
- Use low-mineral water where you can, and never softened water.
Read more
- Bottom watering: how and when
- Tap, rain or filtered water?
- Self-watering pots: pros and cons
- N-P-K: fertilizer numbers explained
- How to fertilize houseplants
- Fertilizer types compared
- White crust on soil? How to flush salts
Sources
- University of Maryland Extension: Fertilizer toxicity or high soluble salts in indoor plants
- University of Maryland Extension: Mineral and fertilizer salt deposits on indoor plants
- UF/IFAS Gardening Solutions: Houseplant care
General guidance, not a diagnosis. For valuable, edible or outdoor crops, check with a local extension service or plant expert. Use any product exactly as its label says, and keep children and pets away while it dries.