Herb · Lamiaceae
Lavender
Lavandula angustifolia
Give it full sun and sharp drainage, leave the soil lean, and lavender pays you back 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 grown for its silvery foliage and fragrant purple spikes. It belongs to the mint family and thrives on neglect, the kind of plant that rewards a sunny, gravelly corner where little else wants to grow. Once it settles in, it stands up to drought and heat with ease.
The secret to keeping it is simple but unforgiving: lavender wants lean soil and sharp drainage above all. Rich ground and a heavy watering can are how most plants are lost, since soggy roots rot fast. Plant it high and dry, water sparingly, and it can live for a decade or more.
It earns its keep beyond the border too. The flower spikes dry well for sachets and cooking, draw bees all summer, and a yearly shear keeps the plant dense and compact instead of bare and woody. Treat it mean, and it keeps its shape and scent for years.
Care
The short version: full sun, lean and sharply drained soil, and very little water once it is established. Prune it every year after it flowers, skip the fertilizer, and never let water pool around the crown.
Light
Give lavender full sun, 6 or more hours a day. Anything less and the plant grows leafy and shy of flowers, leaning toward whatever light it can find. Sun is also what keeps the foliage dry and disease at bay.
Water
Water a young plant weekly only until it roots in, then back right off. 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 in lean, sandy or gravelly ground that drains sharply. A pH of 6.5 to 7.5, neutral to slightly alkaline, suits it well, and loam or shallow rocky soil works too as long as it never stays waterlogged. Rich soil only makes the plant floppy.
Temperature
English lavender is tough, taking anything from -4°F to 95°F (-20°C to 35°C) in zones 5 through 9. Hard winters and cold, wet soil are the real threats, not summer heat.
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 trouble off the leaves.
Feeding
Feed it almost nothing. A thin top-dressing of coarse compost at planting is plenty, and richer feeding just grows soft, floppy stems and weakens the scent. Lean ground gives you the best fragrance.
Pruning
Shear the plant back by a third to a half every year right after it flowers to keep it compact and extend its life. Always stay in the green growth and never cut into the old bare wood, which rarely resprouts.
Repotting
In a container, repot every 2 to 3 years in spring into a pot only a little larger, using a gritty, free-draining mix. Crowded roots, fast-drying soil, and sparse flowering are the signs it has outgrown its pot.
Size & spacing
A mature plant reaches 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 to start from seed and quick to reward patience once planted. Sow indoors in late winter, set young plants out in spring after the last frost, and the purple spikes arrive in early to mid-summer, ready to cut just as the 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. Most of the rest comes from skipping the yearly prune. Match what you see below and fix the conditions, not just the symptom.
Wilting and decline even though the soil stays wet
This is root rot, often driven by Phytophthora, and it is the single most common way lavender dies. The cause is too much water sitting against the roots, not too little, so the cure is sharp drainage rather than more watering. Stop watering, move the plant into a raised mound of gritty soil, and discard any plant whose roots have already gone dark and soft.
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 fails to wake up after winter
A lavender that stays brown in spring has usually taken winter damage, either cold injury in zone 5 and colder or rot from cold, wet soil at the crown. Wait until late spring before giving up, since lavender breaks dormancy late, then cut back to any live green wood you find. Where winters are hard, plant in sharply drained, sheltered ground and lean on 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 woody stems at the base with green only at the tips
A lavender left unpruned turns woody and leggy, its green growth pushed out to the very ends of long bare branches. Shear it back by a third to a half right after flowering, but always stay in the green, since the old wood underneath rarely resprouts. A plant that has already collapsed into bare wood 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
Spotted, yellow, or moldy leaves in damp crowded growth
Damp, still air invites fungal leaf spot, which shows up first deep in a crowded plant where the leaves never dry. Open the plant up with wider spacing and an annual prune, water at the base in the morning, and clear away the affected foliage. Good airflow does more to stop it 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
A green, healthy plant that barely flowers
When a leafy lavender refuses to bloom, the usual culprit is too little sun or too much feeding. Lavender needs six hours or more of direct sun and lean ground, and rich, fertilized soil pushes foliage instead of flowers. Move it into full sun, stop feeding, and prune only after it blooms so you never cut off next year's spikes.
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 in the leaves and 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
The linalool in the oils can bring on drooling, vomiting, and a cat that goes off its food. A nibble usually passes on its own, but the concentrated essential oil is a far greater danger and should never be used on a cat.
Dogs Mild
A dog that chews the leaves or flowers may drool, vomit, or lose its appetite for a while. The plant itself is a minor upset; the bigger risk is undiluted lavender oil.
Horses Mild
Horses can't vomit, so the plant tends to show up as a dull appetite and mild stomach discomfort instead. Small grazed amounts rarely cause more than that.
Rabbits Mild
The same aromatic oils that upset cats and dogs can leave a rabbit off its feed with a queasy gut. Keep it out of the regular diet and offer only the odd sprig.
Livestock Mild
Grazing animals usually leave the strong-smelling foliage alone, and a small taste does little harm beyond a passing stomach upset. Large quantities are the only real concern.
Birds Caution
There is no clear record of harm, but birds are sensitive to strong aromatic oils, so it is safer to keep lavender and especially its oil away from them.
People Culinary use
The dried flowers are a kitchen herb, used in small amounts for baking and tea, and are safe to eat. Leave the concentrated essential oil out of food.
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 mostly in hardiness, size, and how much heat and humidity they can take. These few are the ones you will meet most often.
'Hidcote'
A compact cultivar to about 20 inches (50 cm) with deep violet-blue spikes that has long been a favorite for low edging.
'Munstead'
A compact, cold-hardy heirloom that holds up well in zone 5 gardens where many lavenders struggle.
'Phenomenal' (Lavandula × intermedia)
A vigorous lavandin hybrid with a bushy habit, strong winter hardiness, and unusual tolerance of heat and humidity.
French lavender (Lavandula stoechas / L. dentata)
Easy to spot by its tufted rabbit-ear bracts, but tender to roughly zones 8 to 11, so cold-climate gardeners grow it as an annual or in a pot.
How to propagate
Lavender is easy to multiply from cuttings and slower from seed, and only cuttings keep a named cultivar true to type.
Stem cuttingsEasy
Summer, from non-flowering side shoots · 2-6 weeks to root in warm, moist potting mix
Cuttings are the most reliable way to make more lavender and the only way to keep a named cultivar true. In summer, take a non-flowering side shoot, cut just below a node, strip the lower leaves, and dip the base in rooting hormone. Kept around 70°F (21°C) in moist mix, it 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 expect uneven germination over 2 to 4 weeks, with a full season or more before the plants flower. Named cultivars won't come true from seed, so the seedlings vary.
Myths
Lavender is completely safe for pets because it is a calming herb.
The ASPCA lists lavender as toxic to cats, dogs, and horses, and eating the plant can cause mild nausea, vomiting, and a lost appetite. The concentrated essential oil is the real hazard, particularly for cats, so keep it well away from animals.
Lavender needs rich soil and generous regular watering to thrive.
Lavender does best in lean, sandy, sharply drained soil and shrugs off drought once it settles in. Rich soil and frequent watering bring on floppy growth and root rot, which is the most common way the plant dies.
Hard pruning into the old woody base will rejuvenate a leggy lavender.
Cut into the bare old wood and it rarely sends out new shoots. Prune every year after flowering, taking no more than half and staying in green growth, and replace any plant that has already gone mostly woody.