plantatiousBasil (Ocimum basilicum)
- Light
- Full sun
- Watering
- Keep the soil lightly moist
- Temperature
- 15–30°C
Basil, also called sweet basil and known to botanists as Ocimum basilicum, is a fragrant herb of the mint family, Lamiaceae. It is native to tropical Africa and Asia, which is why it loves warmth and light, and indoors or in cool climates you grow it as a tender annual. Most people grow it for its soft, aromatic leaves, and a healthy plant keeps making new ones for months when you pick it the right way.
How fast does basil grow?
Basil is one of the quickest herbs you can grow: in warm, bright weather you can see new leaves from one week to the next, while in the low light of winter it barely moves.
Light and warmth set the pace. Long, warm days give basil the energy for fast, leafy growth; short, cool days slow it down, and no amount of watering or feeding makes up for missing light. What you do matters too. Pinching out the tips makes the plant branch, so it grows bushier instead of just taller. Once it starts to flower, it puts its energy into seeds and makes fewer new leaves.
How to care for basil indoors
Give basil the sunniest window you have, keep its soil lightly moist, and keep it above 15°C. It wants as much direct sun as you can give it; on a dim windowsill it grows tall and thin, with small, pale leaves. Water when the surface of the soil starts to dry, so it stays lightly moist but never waterlogged, and always use a pot that drains. Cold is the one thing basil cannot take: a chilly draft or cold window glass on a winter night can leave dark, damaged patches on its leaves.
| Light | Full sun |
|---|---|
| Watering | Keep the soil lightly moist |
| Temperature | 15–30°C |
| Native to | China, Japan, Korea and Taiwan, Indian subcontinent, Mainland Southeast Asia, Maritime Southeast Asia, New Guinea region, and Australia |
| Growth form | Annual plant or small shrub |
Sources
- Ocimum basilicum (Basil, Genovese Basil, Purple Basil, Saint Joseph's Wort, Sweet Basil, Thai Basil), NC State Extension
- Basil, Clemson Cooperative Extension
- Growing Herbs Indoors, Penn State Extension
- Govaerts R (ed.). WCVP: World Checklist of Vascular Plants, version 16, Royal Botanic Gardens, Kew, CC BY 3.0
Tips
- Pinch out the growing tips just above a pair of leaves to make your basil bushy.
- Pinch off flower buds as soon as you see them, because flowering slows new leaves.
- Split a crowded supermarket pot into a few smaller clumps and give each its own pot.
- Pick from the top, taking whole tips rather than single lower leaves.
- Feed it lightly with a balanced plant food while it grows fast, and not at all in winter.
Is basil safe for cats and dogs?
Yes. The ASPCA lists basil as non-toxic to both cats and dogs, so a nibbled leaf is no cause for alarm. A pet that eats a lot of any plant can still get an upset stomach, so call your vet if yours keeps vomiting or seems unwell. Concentrated essential oils are a different matter: many can make pets ill, so keep them out of reach.
Growing basil: common questions
Why is my basil wilting?
Most often the soil has dried out: water it well and it usually perks up within hours. If the soil is already wet, the roots may be sitting in water, so let the pot drain and water less often. A cold draft can make it droop too.
Why does supermarket basil die so quickly?
Each pot holds many seedlings crowded together, raised fast in a warm greenhouse. Split it into a few clumps, give each one its own pot and the sunniest spot you have, and it can keep growing for months.
Should I let my basil flower?
Not if you want leaves. Once basil flowers, it puts its energy into seeds, makes fewer new leaves, and the leaves can taste more bitter. Pinch off the buds as they appear, or let one plant flower for the bees if you grow it outdoors.
Can I grow basil indoors in winter?
Yes, but expect it to grow slowly. Give it the brightest window you have, keep it away from cold glass, water less often and pick lightly until the days grow longer again. A grow light helps a lot if your windows are dim.