# Nutrient burn

> Nutrient burn is browning and crisping of leaf tips, then margins, caused by a root-zone salt concentration (EC) higher than the plant can handle.

- Canonical: https://genetixbay.com/knowledge/glossary/nutrient-burn.html
- Also written: nute burn, nute-burn, tip burn, burnt tips, fertiliser burn, fertilizer burn, overfert
- Glossary category: Nutrients · Evidence: Established
- Status: Draft: awaiting expert review · Updated: 2026-10-31
- Licence: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/), attribute "GenetixBay cannabis glossary"

Nutrient burn is leaf damage from excess total salts in the [root zone](https://genetixbay.com/knowledge/glossary/root-zone.md). As [EC](https://genetixbay.com/knowledge/glossary/ec.md) climbs, water uptake slows, and salts build up at the leaf tips and edges where water evaporates. The tips yellow, then turn brown and crisp, and the damage creeps inward along the margins. It is a general salt effect, not a single-element [toxicity](https://genetixbay.com/knowledge/glossary/nutrient-toxicity.md).

## In practice

Typical triggers are feeding above the plant's tolerance, letting a coco or rockwool slab dry back hard so EC concentrates, skipping [runoff](https://genetixbay.com/knowledge/glossary/runoff.md) in containers, or stacking additives on a full-strength base. Check runoff EC against input EC: runoff much higher than input means salts are accumulating. Lower the [feed strength](https://genetixbay.com/knowledge/glossary/input-ec.md) or [water to runoff](https://genetixbay.com/knowledge/glossary/watering-to-runoff.md). In serious build-up, a [root-zone flush](https://genetixbay.com/knowledge/glossary/root-zone-flush.md) to wash salts out of the medium is the valid fix. A slight tip burn in late flower on heavily fed plants is common and usually harmless.

## Don't confuse with

- **Heat or light burn**: bleaching or crisping at the top of the canopy closest to the lamp.
- **Potassium deficiency**: margin burn on older leaves with yellowing first.
- **Chloride or boron toxicity**: specific elements, often from water.

## Myth check

A root-zone flush treats the medium, not the plant, and is not a pre-harvest ritual. See [the flush debate](https://genetixbay.com/knowledge/harvest-cure/flush-debate.md).

## Related terms

[Nutrient toxicity](https://genetixbay.com/knowledge/glossary/nutrient-toxicity.md), [Feed chart](https://genetixbay.com/knowledge/glossary/feed-chart.md), [ppm of an element](https://genetixbay.com/knowledge/glossary/elemental-ppm.md), [Nutrient deficiency](https://genetixbay.com/knowledge/glossary/nutrient-deficiency.md)

## Read more

- [Brown or burnt leaf tips on cannabis: a differential](https://genetixbay.com/knowledge/diagnosis/brown-burnt-tips.md)
- [Runoff testing: how to measure root-zone pH and EC and what the numbers mean](https://genetixbay.com/knowledge/ph-ec/runoff-testing.md)

## Sources

1. Sonneveld C, Voogt W. 2009. Plant Nutrition of Greenhouse Crops. Springer. https://doi.org/10.1007/978-90-481-2532-6
2. Cockson P, Landis H, Smith T, Hicks K, Whipker BE. 2019. Characterization of nutrient disorders of Cannabis sativa. Applied Sciences 9(20):4432. https://doi.org/10.3390/app9204432