Spearmint
Mentha spicata
A fragrant perennial herb with bright green serrated leaves and a sweeter, milder flavor than peppermint. Fast-growing in sunny pots when soil stays moist and you pinch often for a fuller plant. Keep away from pets that chew.
Light
Full Sun
Water
High
Difficulty
Easy
Humidity
Moderate
Pet Warning
Spearmint contains essential oils that are toxic to dogs, cats, and horses. Ingestion can lead to vomiting, diarrhea, and gastrointestinal distress.
Care Notes
Light
Spearmint thrives in bright light. A south window or grow lights work best. Partial shade is possible, but stems stretch and scent fades.
Water
Keep the soil consistently moist. Do not let it dry out completely, but use a pot with drainage holes so roots are not waterlogged.
Soil
A rich, moist, well-draining mix with a pH around 6.0-7.5 suits it. Mint spreads by runners, so a dedicated planter keeps it contained.
Humidity & Temperature
Prefer about 55-75°F. Average household humidity is usually enough; boost it in dry winters with a humidifier or pebble tray.
Common Issues
Leggy growth means more light or more pinching. Pinch flower spikes to keep flavor in the leaves. Watch for spider mites and aphids; if you harvest for food, use food-safe treatments such as insecticidal soap or neem.
In-Depth Care & Growth
Feeding & Soil
Fertilizer
Balanced liquid 10-10-10 fertilizer
Soil
Rich, moist, well-draining potting mix with a pH between 6.0 and 7.5.
Physical Attributes
Mature Size
12 to 24 inches
Growth Rate
Fast
Propagation
Stem cuttings in water, root division, or transplanting runners (rhizomes).
Common Varieties
Kentucky Colonel
Large bright green lance-shaped leaves with a deeply crinkled texture and sharply serrated edges.
Moroccan Spearmint
Bright green, highly textured, crinkled oval leaves with sharply serrated margins.
Spearmint 'Nana'
Compact clusters of small bright green leaves with a crinkled texture and finely serrated edges.