Troubleshooting
Spearmint problems — and how to fix them
Spearmint (Mentha spicata) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Invasive spreading
Runners overrun beds within a season. Grow in a sunken pot or barrier, or in a standalone container, to keep it contained.
Mint rust
Orange pustules appear on leaf undersides. Remove and destroy affected stems, improve airflow, and avoid overhead watering; severe cases may need replacing the plant.
Woody, sparse growth over time
Old clumps become congested and less flavourful. Lift and divide every 2-3 years and cut back hard to rejuvenate fresh leaf.
Drying out
Mint wilts fast in dry soil, especially in pots. Keep the soil consistently moist and shade the roots in hot weather.
Prevent spearmint problems before they start
Most spearmint issues are care-mismatch, not bad luck. Dial in the basics:
Looking for spearmint in general rather than its problems? Read the full spearmint care guide — light, water, soil and feeding.
Spearmint problems — FAQ
Why is my spearmint invasive spreading?
Runners overrun beds within a season. Grow in a sunken pot or barrier, or in a standalone container, to keep it contained.
Why is my spearmint mint rust?
Orange pustules appear on leaf undersides. Remove and destroy affected stems, improve airflow, and avoid overhead watering; severe cases may need replacing the plant.
Why is my spearmint woody, sparse growth over time?
Old clumps become congested and less flavourful. Lift and divide every 2-3 years and cut back hard to rejuvenate fresh leaf.
Why is my spearmint drying out?
Mint wilts fast in dry soil, especially in pots. Keep the soil consistently moist and shade the roots in hot weather.