Rosemary
Salvia rosmarinus · Perennial
The most commonly killed indoor herb. Rosemary wants dry roots, moving air and as much light as you can give it. It dies from kindness far more often than neglect.
What it needs indoors
- Light
- Full sun6–8 hours direct sun
- Water
- Let it dry outLet the top inch dry out first
- Temperature
- 60–70°F
- Growing medium
- Sharply draining, sandy mix
- Native range
- Mediterranean limestone coast
- Difficulty
- Enthusiast
What usually goes wrong
A whole branch goes grey-brown and the needles come off in your hand
Root rot, usually traced back to a saucer nobody empties. By the time the top of the plant shows it the roots have been dying for weeks.
Fix: Empty the saucer every time you water and only water when the top inch is genuinely dry. Terra cotta rather than glazed or plastic. A plant this far along rarely comes back, so take cuttings from whatever green growth is left.
Dusty white coating on the stems and the undersides of the needles
Powdery mildew. Rosemary likes humid air but not still air, and a closed warm room with nothing moving through it hands the fungus everything it needs.
Fix: Open a window, space the pots apart, or run a small fan on low nearby for a few hours a day. Cut out the worst stems. Watering the soil rather than the foliage helps.
Long bare stems with needles only at the ends
Weak light and no pruning. Indoors it grows towards whatever light it can find and abandons everything behind it.
Fix: The brightest window you have, or a grow light for 12 hours, and turn the pot every few days. Pinch the tips through the growing season so it branches instead of running.
