Herb · Lamiaceae
Lavender
Lavandula angustifolia
Give it full sun and sharp drainage, keep the soil lean, and lavender rewards you with fragrance for years.
Full sun
Every 10–21 days
USDA 5–9
18–35 in · 45–90 cm
Overview
Lavender is a Mediterranean subshrub built from narrow, silvery gray-green leaves and slender purple flower spikes. It belongs to the mint family, and up close the whole plant is dry and aromatic to the touch, the foliage fine and almost dusted-looking rather than glossy. Once its roots take hold, it stands up to drought and heat without complaint.
What keeps it alive is simple and strict: lavender wants lean soil and sharp drainage above all. Rich ground and heavy watering are how most plants are lost, since the roots rot fast once they sit wet. Planted high and dry and watered with a light hand, a single plant can live a decade or more.
The flowers are its signature. Straight, wiry stems lift the spikes above the mound, each one crowded with small purple buds that open into the fragrant bloom, and a yearly shear holds the plant dense and compact instead of letting it go bare and woody. The dried spikes keep their color and scent, and bees work them all summer.
Care
The short version: full sun, lean and sharply drained soil, and very little water once the plant is established. Prune it each year after it flowers, skip the fertilizer, and never let water pool around the crown.
Light
Lavender wants full sun, 6 or more hours a day. In less light the fine gray foliage grows loose and leafy and the plant leans toward the brightness, raising few spikes. Direct sun also keeps the leaves dry and holds disease off.
Water
Water a young plant weekly only until it roots in, then ease right back. A mature lavender is drought-tolerant and wants no more than about half a gallon every couple of weeks, if that. Soggy soil is the fastest way to kill it.
Soil
Plant it in lean, sandy or gravelly ground that drains sharply. A pH of 6.5 to 7.5, neutral to slightly alkaline, suits it, and loam or shallow rocky soil works too, so long as it never stays waterlogged. Rich soil only makes the stems soft and floppy.
Temperature
The fine silvery foliage is hardier than it looks: English lavender rides out -4°F to 95°F (-20°C to 35°C) within zones 5 through 9. What browns and kills the plant is a hard winter over cold, wet ground, not the blaze of summer.
Humidity
Lavender likes it dry, around 30% to 50% humidity, and resents muggy, still air. Where summers run humid, wide spacing and good airflow keep fungal spotting off the narrow leaves.
Feeding
Feed it almost nothing. A thin top-dressing of coarse compost at planting is plenty, and richer feeding grows soft, floppy stems and weakens the scent held in the foliage. Lean ground gives the strongest fragrance.
Pruning
Shear the plant back by a third to a half each year, right after it flowers, to keep the mound tight and extend its life. Stay in the soft green growth and never cut into the hard gray old wood, which rarely resprouts.
Repotting
In a container, repot every 2 to 3 years in spring into a pot only a little larger, with a gritty, free-draining mix. Roots circling the pot, fast-drying soil, and sparse flowering show it has outgrown its home.
Size & spacing
A mature plant forms a mound about 18 to 35 inches (45 to 90 cm) tall and roughly 24 to 35 inches (60 to 90 cm) across. Give each one that much room so air moves freely and the leaves stay dry.
When to plant
Lavender is slow from seed and rewards patience once planted. Sow indoors in late winter, set the young plants out in spring after the last frost, and by early to mid-summer the purple spikes rise on their wiry stems, best cut just as the small buds begin to open.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: late winter, 10-12 weeks before last frost; germination is slow and erratic
- Plant: spring after the last frost, once soil has warmed and drains freely
- Harvest: Purple flower spikes appear early to mid-summer; harvest spikes just as the buds begin to open for the strongest fragrance, and dry in a cool airy place
Hardiness
USDA hardiness zones: 5–9
Temperature: down to -29°C
Troubleshooting
Almost every lavender problem traces back to too much water or too little sun, with most of the rest owing to a missed yearly prune. Match what you see on the plant below and fix the conditions rather than the symptom.
Wilting and decline even while the soil stays wet
When the silvery mound sags over ground that stays wet, the trouble is root rot, often the Phytophthora kind, and it kills more lavender than anything else. Underground the roots turn dark, soft, and slick where firm pale roots should be, brought on by water pooling against them rather than any thirst. Stop watering, lift the plant onto a raised mound of gritty soil, and discard any whose roots have already gone black and mushy.
Fix:
- Stop supplemental watering immediately
- Replant into a raised bed, mound, or gritty sharply draining soil
- Discard plants with extensively rotted roots rather than trying to save them
The whole plant stays brown and bare in spring
A lavender still standing brown and brittle as spring comes on has usually taken winter damage, whether cold injury in zone 5 and colder or rot that turns the crown soft and dark under cold, wet soil. Snap a stem and look: dry wood with no green streak beneath the bark means dead growth. Lavender wakes late, so wait until late spring, cut back to any live green wood, and in hard-winter ground plant sharply drained and sheltered with tough cultivars like 'Munstead' or 'Phenomenal'.
Fix:
- Wait until late spring before removing the plant, since lavender breaks dormancy late
- Cut back to any live green wood found
- Replace dead plants, choosing hardy cultivars such as 'Munstead' or 'Phenomenal'
Bare gray stems below, green tufts only at the tips
Left unpruned, lavender goes woody and leggy, its base thickening into knotted gray stems while the last silvery leaves cling only to the outer tips. Shearing it back by a third to a half right after flowering pulls the green mound back over that bareness, as long as the cuts land in the soft green and stay clear of the hard old wood, which rarely breaks bud again. A plant already sprawled into naked stems is best replaced from cuttings.
Fix:
- Shear back by one-third to one-half into green growth right after flowering
- Stay above the old bare wood, which rarely resprouts
- Replace very old, collapsed plants with new ones from cuttings
Blotched, yellowed, or fuzzy gray foliage deep in a crowded, damp plant
Damp, still air breeds fungal leaf spot, and it stains the leaves first in the crowded shade at the plant's heart, where the narrow gray-green blades never dry. Discolored blotches and a grayish fuzz creep over foliage that should be clean and silvered. Open the plant with wider spacing and a yearly prune, water at the base in the morning, and strip away the marked leaves, since moving air clears it faster than any spray.
Fix:
- Thin and space plants to improve air circulation
- Water at the base in the morning, keeping foliage dry
- Remove and dispose of affected foliage and debris
Full green foliage but almost no spikes
A plant thick with silvery leaves yet showing scarcely a purple spike is telling you it has too little sun or too much feeding. Lavender raises its flower spikes only on six hours or more of direct sun and lean ground, while rich, fertilized soil swells the foliage and swallows the bloom. Move it into full sun, stop feeding, and prune only after flowering so the wood that carries next year's spikes is left standing.
Fix:
- Move or transplant to a spot with 6+ hours of direct sun
- Stop fertilizing and let the soil stay lean
- Prune only after flowering so next season's bloom wood is not removed
Toxicity
Lavender is a mild hazard for animals rather than a serious poison. The oils packed into its gray leaves and purple flowers, mainly linalool and linalyl acetate, can upset a pet's stomach if eaten in quantity, and the concentrated essential oil is far more dangerous than the plant itself. For people the dried flowers are a culinary herb, safe in small amounts.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds
Safe for
People
Cats Mild
A cat that mouths the aromatic gray leaves takes in linalool from the oils and may drool, vomit, or turn from its food. One nibble usually passes on its own, but the concentrated essential oil is a far graver danger and should never touch a cat.
Dogs Mild
A dog that crushes the leaves or purple spikes between its teeth may drool, vomit, or go off its food for a while. The plant itself is a minor upset; the sharper risk is undiluted lavender oil.
Horses Mild
Unable to vomit, a horse shows it instead as a dull appetite and mild stomach discomfort. Small grazed mouthfuls of the strong-scented foliage seldom go further.
Rabbits Mild
The same aromatic oils that unsettle cats and dogs leave a rabbit off its feed with a queasy gut. Keep the fragrant sprigs out of the regular diet and offer only the odd one.
Livestock Mild
Grazing animals mostly turn from the pungent gray-green foliage, and a small taste does little beyond a passing stomach upset. Only large quantities give real cause for concern.
Birds Caution
No harm is on record, yet birds are sensitive to strong aromatic oils, and the scent locked in the leaves and flowers is potent, so keep lavender and its oil away from them.
People Culinary use
The dried purple buds are a kitchen herb, safe to eat in small amounts in baking and tea, carrying the plant's scent into the food. The concentrated essential oil, though, stays out of the kitchen.
The garden plant is a mild hazard, but concentrated lavender essential oil is far more dangerous, especially to cats - never apply oil to pets or let them ingest it.
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
Lavenders differ in hardiness and size and in how much heat and humidity they take, and in the depth of color and shape of their spikes. These few turn up most often.
'Hidcote'
A compact form of about 20 inches (50 cm) carrying dense spikes of deep violet-blue, long grown as a low edging.
'Munstead'
A compact, cold-hardy heirloom that stays sturdy through zone 5 gardens where many lavenders give out.
'Phenomenal' (Lavandula × intermedia)
A full, bushy lavandin hybrid with strong winter hardiness and an uncommon tolerance of heat and humidity.
French lavender (Lavandula stoechas / L. dentata)
Easy to know by the tufted rabbit-ear bracts perched atop its spikes, though it is tender to roughly zones 8 to 11 and grown in cold climates as an annual or in a pot.
How to propagate
Rooting a soft green side shoot is the quick road to more lavender, while seed is the slow one, and only a cutting reproduces a named cultivar faithfully.
Stem cuttingsEasy
Summer, from non-flowering side shoots · 2-6 weeks to root in warm, moist potting mix
Cuttings are the surest way to raise more lavender and the only way to keep a named cultivar true to type. In summer, take a non-flowering side shoot with soft green growth, cut just below a node, strip the lower leaves, and dip the pale cut base in rooting hormone. Kept around 70°F (21°C) in moist mix, it puts out roots in about 2 to 6 weeks.
SeedModerate
Sow indoors in late winter, 10-12 weeks before last frost · 2-4 weeks to germinate; plants take a full season or more to reach flowering size
Seed is the slower, less certain route. Sow indoors in late winter, 10 to 12 weeks before the last frost, and watch for uneven germination over 2 to 4 weeks, the small seedlings taking a full season or more before they raise any spikes. Named cultivars will not come true from seed, so the plants vary.
Myths
The calming scent of lavender means the whole plant is safe for pets to chew.
The ASPCA lists lavender as toxic to cats, dogs, and horses, and eating the aromatic leaves and flowers can bring mild nausea, vomiting, and a lost appetite. The concentrated essential oil is the real hazard, cats most of all, so keep it well away from animals.
Lavender flourishes only when its soil is rich and its watering steady and plentiful.
Lavender is at its best in lean, sandy, sharply drained soil and shrugs off drought once its roots take hold. Rich soil and frequent watering bring floppy growth and root rot, which is the most common way the plant dies.
Cutting an old leggy lavender far down into its gray woody base spurs vigorous new shoots.
Cut into the hard gray old wood and it rarely pushes fresh shoots. Prune every year after flowering, taking no more than half and staying in the soft green growth, and replace any plant already gone mostly woody.