Environment & care

Fertiliser & salt burn

Also called: tip burn, salt build-up

Brown crispy leaf tips and margins with a white crust on the soil or pot rim from accumulated salts.

What you'd see

Brown, dry tips and edges, often with a thin yellow band between dead and living tissue
White or tan crust on the soil surface, pot rim or drainage holes
Wilting shortly after feeding; stunted growth despite regular fertiliser

Where to look

Plants fed on schedule regardless of growth, watered with small sips that never flush, or given hard tap water for years.

How it spreads

Not infectious.

Is it really this? Look-alikes

Low humidity — Dry-air tip burn has no crust and improves with humidity.
Underwatering — Thirst crisps the whole leaf edge and the pot is light.
Fluoride sensitivity — Dracaena and spider plants tip-burn from fluoridated water even without feeding.

What's going on

Fertilisers are salts. Salts draw water out of root cells by osmosis; too concentrated and the roots dehydrate even in wet soil. Tips and margins die first because they are furthest along the plumbing.

Small waterings evaporate and leave the salts behind, so they climb over months even at 'safe' feeding rates.

Why?

Once you see fertiliser as salt, two rules follow: feed when the plant is actually growing, and water thoroughly enough now and then to rinse the salts out of the bottom. Feeding more can never fix a plant that looks hungry from salt.

Grandmother's remedies

What people have always done — with an honest note on each.

The big flush
Water slowly until it runs freely from the bottom, wait, and do it twice more. Let it drain fully.
Verdict: The cure. Do it every couple of months if you feed regularly.
Scrape the crust
Remove the crusted top layer and replace with fresh mix.
Verdict: Helpful alongside a flush.
Rainwater
Collect rainwater for fluoride- and salt-sensitive plants.
Verdict: Genuinely helps dracaena, calathea and spider plants.

Modern remedies

What growers and extension services reach for today.

Half-strength feeding
Dilute to half the label rate, only while the plant is producing new leaves.
Verdict: Best practice for almost every houseplant.
Filtered or distilled water for sensitive species
Use for calathea, dracaena, carnivorous plants.
Verdict: Effective for the few species that need it.

Honest verdict

Brown tips do not turn green again. Trim them if you like, following the leaf's natural shape and leaving a hair of brown so you do not open a fresh wound.

Prevention

Feed less than the label says
Flush pots every few months
Do not feed dormant or sick plants
Empty saucers

Plants this commonly troubles

Pothos Snake plant Fiddle-leaf fig