Lavender
Lavandula spp. · Perennial
Temperamental indoors because it wants hot, arid conditions and resents humidity. Drainage is the single biggest factor in whether it survives.
What it needs indoors
- Light
- Full sunAs much direct sun as possible
- Water
- Let it dry outSparingly; let the soil dry out
- Temperature
- 60–70°F
- Growing medium
- Gritty and sharply draining, with added perlite
- Native range
- Hot, dry rocky slopes of the western Mediterranean
- Difficulty
- Enthusiast
What usually goes wrong
Stems go grey from the bottom up and then the whole plant goes off at once
Lavender comes off hot dry rock, and ordinary potting compost holds more water than the plant has ever had to deal with. The roots end up sitting in it.
Fix: Repot into a mix that is at least a third grit or perlite, in terra cotta with a decent drainage hole. Water it properly, then leave it until the pot feels light in your hand.
Plenty of leaf, no flowers
It wants more hours of direct sun than a window normally delivers before it will set buds at all.
Fix: The sunniest south-facing sill in the house, or a strong grow light for 12 hours. Even then, expect foliage more often than flowers. Many people keep it inside over winter and put it out in summer to bloom.
Cut back hard, and the stems never resprout
Old lavender wood carries no dormant buds. A stem cut below the green growth is finished.
Fix: Prune every year after flowering, taking around a third and always leaving green leaf below the cut. A plant already cut into bare wood will not recover from it, so start again from a cutting.
