Herb · Lamiaceae
Mint
Mentha spicata
Give it steady moisture and a pot of its own, and mint keeps the fresh leaves coming from spring to frost.
Partial shade
Every 2–4 days
59–77°F · 15–25°C
80–90 days
Overview
Mint just about grows itself, which is what makes it such a rewarding herb to keep, and the same drive is its one catch. It runs in the Lamiaceae family beside basil and sage, all built on those tell-tale square stems, and the kind that shows up in most gardens is spearmint. Crush a single leaf and that cool, sweet rush of scent tells you exactly what you have.
The thing that really sets mint apart is its appetite for ground. It flings out runners above and below the soil, and every one roots and launches a new plant, so one small sprig can fill a whole bed in a season. That drive makes it nearly impossible to kill off, and it is the reason keen growers plant it in a pot or a sunken, bottomless container instead of turning it loose.
Mint pulls its weight far past the kitchen, too. As a hardy perennial it storms back year after year in cool and mild climates, laughs off neglect, and drops a few leaves into tea, salads, and summer drinks. Hand it damp soil and a little shade and it powers on with almost no fuss.
Care
The short version: mint wants part shade and rich, evenly moist soil, a regular pinch to keep it bushy, and a container or edged bed to rein the runners in before they take off.
Light
Mint thrives in partial shade, especially where summers crank up the heat, though it takes full sun as long as you keep the soil moist. Park it where morning light meets some afternoon cover and it rewards you with tender, full-flavored leaves.
Water
Keep the soil consistently moist and never let the root zone dry out, since mint wilts fast the moment it goes thirsty. In warm weather or a pot that means a drink every 2 to 4 days, and step it up the second the leaves start to droop.
Soil
Drop it into rich, moist, well-draining loam loaded with organic matter and it takes off. A pH from 6.0 to 7.0 suits it perfectly, which covers most ordinary garden soil.
Temperature
Mint hits its stride between 59°F and 77°F (15°C to 25°C), the cool-to-mild range it came from. It shrugs off heat with enough water but slows down and toughens its leaves once things get too hot.
Humidity
Average humidity around 40% to 70% keeps mint cruising, and outdoor air usually lands right in that band. Dry indoor air rolls out the welcome mat for spider mites, so a potted plant loves a little extra moisture nearby.
Feeding
Mint runs on almost nothing at the table. A balanced all-purpose fertilizer or a light topping of compost in spring fuels the whole season, and overfeeding just waters down the flavor.
Pruning
Pinch the growing tips often to keep the plant bushy and grab leaves as you go. Snap off flower spikes the moment they appear so the leaves hold their peak taste, and cut the plant back hard after it flowers to drive out fresh tender growth.
Repotting
A potted mint packs itself with roots and runners fast, so divide and repot it once a year or the second the container jams up. Ditch the woody center, keep the vigorous outer pieces, and fire them into fresh soil.
Size & spacing
Mint shoots up 12 to 35 inches (30 to 90 cm) tall and sprawls 2 to 4 feet (60 to 120 cm) wide, often wider once the runners let rip. Hand it real room, or better a container, so it never crowds its neighbors.
When to plant
Mint laughs off cold once it gets going, but young plants want a settled spring to launch from. Start seed indoors 6 to 8 weeks before the last frost, plant out once the hard frosts clear, then pick leaves right through the growing season.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: 6-8 weeks before last spring frost
- Plant: Spring, after danger of hard frost has passed
- Harvest: Harvest leaves throughout the growing season; pinch off flower spikes for the best leaf flavor
Hardiness
USDA hardiness zones: 3–8
Temperature: down to -40°C
Troubleshooting
Mint is a tough grower, so nearly all its hiccups trace back to wet crowded leaves, a hot dry stretch, or the plant blasting past its space. Match what you see below and jump on it early, while a quick fix still knocks it out.
Orange-brown pustules on the leaf undersides
Spot orange flecks under the leaves and you have caught mint rust, a fungus that pounces when foliage stays wet and the air goes still. Strip off the marked leaves and bin them, never compost, then open up the plant so it dries fast and send your water straight to the soil. Hit a heavily covered plant by cutting it to the ground and clearing the debris, and it bounces right back with a fresh flush.
Fix:
- Remove and destroy infected foliage (do not compost)
- Improve air circulation by thinning growth
- Avoid overhead watering and keep foliage dry
- Cut affected plants to the ground and dispose of debris in severe cases
Mint charging across the bed
This is mint firing on all cylinders. It races outward on underground and surface runners and will claim a whole bed in one season given the chance. Chase each stray shoot back to its runner and dig it out, then plant into a sunken bottomless pot or a deeply edged bed so those eager runners run straight into a wall.
Fix:
- Dig out and sever stray runners
- Grow mint in a sunken bottomless pot or contained bed to restrict spread
- Edge the planting deeply to block runner travel
Potted mint stalling with smaller leaves
A pot of mint packs itself with roots and runners quicker than almost any herb going, and once it turns rootbound the soil drains dry in hours and the leaves shrink. Pop it out of the pot and a dense circling mat spills into view. Split the clump, ditch the woody center, and drop the strong outer pieces into fresh soil to fire it back into growth.
Fix:
- Divide the clump and replant divisions
- Repot into fresh soil in a larger container
- Discard the woody center and keep vigorous outer growth
Speckled, dusty leaves with faint webbing
Hot, dry air rolls out the welcome mat for spider mites, tiny feeders that drain the leaves to a dusty, stippled gray. Catch them fast by tapping a leaf over white paper and watching the specks scurry. Blast the foliage with a strong jet of water to knock them loose, keep the soil moist and the air humid to shut the door on them, and bring in insecticidal soap only if they dig in.
Fix:
- Spray foliage with a strong jet of water to dislodge mites
- Increase humidity and keep soil evenly moist
- Apply insecticidal soap if infestation persists
Toxicity
Mint is a kitchen herb people eat by the handful, and it poses little threat to animals. The essential oils can hand a pet a mild stomach upset if it grazes a big load, so keep grazing in check. The one real warning is pennyroyal, a poisonous relative you must never mix up with garden mint or grow around animals.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds
Safe for
People
Cats Mild
One quick nibble does nothing at all, but a cat that plows through a pile of leaves can drool and bring some up. The essential oils drive that reaction, so it stays mild and clears the moment the plant lands out of reach.
Dogs Mild
Most dogs sniff and stroll off. A dog that chews through a patch can pick up an upset stomach with vomiting or loose stools, and it usually rights itself without help.
Horses Mild
A horse has to tuck into a real mouthful before the oils register. When it does, expect mild colic and loose droppings rather than anything alarming.
Rabbits Mild
A leaf or two goes down fine, but the punchy oils can leave a rabbit gassy and loose if it clears a whole heap. Keep mint to the odd small treat and everyone stays happy.
Livestock Mild
Goats, sheep, and cattle mostly steer clear, thrown off by the sharp scent. One that does work through a stand may show some digestive upset, though it stays minor.
Birds Caution
Solid data on birds and mint runs thin, so play it safe here. Hand over just a small leaf now and then and skip concentrated mint oil altogether.
People Safe
Mint powers all sorts of kitchens, eaten fresh, dried, and brewed into tea with zero trouble. The one catch is its lookalike pennyroyal, which really is poisonous, so never mix up the two.
Common garden mint (Mentha spicata) causes only mild GI signs, but its dangerous relative pennyroyal (Mentha pulegium) contains high levels of pulegone and is seriously toxic, capable of causing liver damage in pets and people; do not confuse or substitute the two.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
United Kingdom
Animal PoisonLine: 01202 509000 (fee applies)
Australia
Animal Poisons Helpline: 1300 869 738
Varieties
Dozens of mints exist, but a handful do the real work in the kitchen and garden. These are the ones worth learning by name.
Spearmint (Mentha spicata)
Spearmint is the everyday kitchen workhorse, flashing bright green pointed leaves and a sweet, mild flavor that carries cooking and cold drinks with ease.
Peppermint (Mentha × piperita)
Peppermint springs from a natural cross of spearmint and water mint, loading up on menthol for a punchier, cooler hit on the tongue.
'Kentucky Colonel' Spearmint
This big-leaved spearmint is the one bartenders grab first when they get to muddling mint juleps.
How to propagate
Mint multiplies like it cannot help itself, so one plant hands you every copy you could want. Take cuttings or split a clump instead of sowing seed, since seed-grown mint rarely tastes like its parent.
DivisionEasy
Spring or early fall · 2 to 4 weeks
Division is the surefire route to keep a named mint tasting exactly like its parent. Come spring or early fall, heave up an established clump and pull or cut it into pieces that each grab roots and runners, then plant them straight back. Water them in and the divisions dig in within 2 to 4 weeks and start pushing out fresh growth.
Stem cuttingsEasy
Spring through summer · 1 to 2 weeks to root
Cuttings practically root themselves from spring through summer. Snip 10 to 15 cm (4 to 6 inch) stem tips, plunge them into water or press them into moist soil, and roots break out in 1 to 2 weeks. Leave seed out of it, since it comes up patchy and the flavor rarely runs true.
Myths
Every kind of mint is dangerously poisonous to pets and should never grow near animals.
Shake off that worry and get growing. Garden mint scores only a mild rating from the ASPCA, and the worst a grazing pet lands is a passing stomach upset. The genuine threat is its relative pennyroyal, whose pulegone can damage the liver. Grow everyday spearmint freely, and just keep pennyroyal well away from animals.
Mint is a tidy, well-behaved herb you can drop in anywhere in the garden.
Not a chance. Mint charges out on runners above and below the soil and swamps a bed in a single season. Plant it in a buried bottomless pot or a sharply edged bed and it stays put, but set it loose in open ground and you will pull stray shoots for years.