Rosemary is the herb that rewards neglect. A woody Mediterranean evergreen, it evolved on dry, rocky hillsides in full sun, which means the things that kill most herbs — lean soil, infrequent watering, baking heat — are exactly what rosemary wants. The number one way gardeners lose rosemary is by being too kind to it: rich soil, frequent watering, and a pot with poor drainage rot the roots fast. Treat it tough and a single plant becomes a fragrant woody shrub that lasts for years, even decades in mild climates. This guide covers how to plant rosemary in the ground or a pot, the watering and pruning routine that keeps it healthy, how to overwinter it where it isn’t hardy, and how to make new plants for free from cuttings.
In this guide
Key Takeaways
- Rosemary demands full sun (6–8+ hours) and fast-draining, gritty, lean soil — wet feet are its number one killer.
- Water sparingly: let the soil dry between waterings. It’s drought-tolerant once established and hates being overwatered.
- Most rosemary is hardy only to about USDA zone 7–8; in colder zones, grow it in a pot and bring it indoors for winter.
- Prune lightly after flowering to keep it bushy, but never cut into bare old wood — it won’t resprout from it.
- It’s easiest to start from a transplant or cutting; seed is slow and unreliable.
Understanding rosemary
Rosemary (now classified as Salvia rosmarinus, long known as Rosmarinus officinalis) is a perennial evergreen shrub, not an annual herb you replant each year. In the right climate it grows into a 2–4 foot woody bush that lives for many years. There are two broad habits worth knowing: upright types like "Tuscan Blue," "Arp," and "Salem" that grow tall and are best for hedging, cooking, and topiary; and trailing or prostrate types like "Prostratus" that spill over walls and containers. If cold hardiness matters to you, "Arp" and "Hill Hardy" are the toughest, surviving into zone 6 with protection, while most varieties are reliably hardy only to zone 7 or 8.
Sun and location
Give rosemary full sun — 6 to 8 hours minimum, and more is better. It will tolerate light shade but grows leggy, sparse, and far less aromatic without strong light. Outdoors, a hot, sunny spot against a south-facing wall is ideal; the reflected heat mimics its native conditions and helps it through marginal winters. Good air circulation matters too, since the one thing rosemary won’t forgive is dampness sitting around its foliage and roots. Avoid low spots where cold air and moisture pool.
Soil: drainage above all
If you remember one thing, make it this: rosemary needs sharp drainage. It thrives in lean, sandy or gritty soil and rots in heavy, rich, wet ground. Aim for a pH of 6.0–7.5 — slightly alkaline is fine. In garden beds with clay, amend heavily with coarse sand and grit, or better yet plant in a raised bed or mound so water drains away from the crown. Do not dig in lots of compost or manure; overly rich soil produces soft, weak growth and weak flavor. Rosemary actually prefers to grow a little hungry.
For containers, use a gritty mix: a quality potting soil cut with 25–30% coarse sand, perlite, or fine gravel. A cactus/succulent mix works well straight from the bag. The pot must have drainage holes, and skip the saucer of standing water.
Planting rosemary
The simplest route is to buy a young plant or start from a cutting — rosemary grows very slowly and unreliably from seed (germination is poor and can take weeks), so few gardeners bother. Plant out transplants in spring after frost, spacing upright varieties 2–3 feet apart to allow for their mature shrub size and the airflow they need. Set the plant at the same depth it grew in its pot, firm it in, and water once to settle the roots. After that, back off the water and let the plant adjust to lean conditions.
Watering: less is more
This is where good intentions kill rosemary. The plant is drought-tolerant once established and wants the soil to dry out between waterings. In the ground, a mature rosemary rarely needs watering at all outside of extended drought — natural rainfall usually suffices. A newly planted one needs occasional water for the first season while it roots, then weans off. Overwatering causes yellowing, blackened roots, and sudden collapse, and is far more common and more fatal than underwatering.
Container rosemary needs more attention simply because pots dry faster, but the rule still holds: water only when the top inch or two of mix is dry, then water thoroughly and let it drain completely. In winter, when the plant is barely growing, cut watering way back. If you’re ever unsure, wait — rosemary recovers from dry far more easily than from wet.
Feeding
Rosemary needs little feeding. In the ground, an annual top-dressing of compost in spring is plenty. In containers, where nutrients leach out, a light feeding with a diluted balanced fertilizer once in spring and again in early summer keeps it healthy, but go easy — overfeeding produces lush, floppy, less flavorful growth. Yellowing leaves on a well-drained plant can indicate it wants a small feed, but always rule out overwatering first, since that causes identical symptoms.
Growing rosemary in containers and indoors
In cold climates, growing rosemary in a pot is the practical way to keep it alive year to year — you garden with it outdoors in summer and move it in before hard frost. Use a pot only slightly larger than the root ball (rosemary dislikes a huge, slow-draining soil volume), with that gritty mix and good drainage. Container plants need repotting every year or two as they grow.
Indoor rosemary is notoriously tricky and most failures trace to two causes: too little light and overwatering. Give it your brightest window — a south-facing sill — or supplement with a grow light, since rosemary craves intense light it rarely gets indoors. Keep it cool (it likes the 50–65°F range in winter, not a warm dry room), provide air circulation to fend off powdery mildew, and water only when the top of the mix dries. A small fan and a cool, bright room go a long way toward keeping a potted rosemary alive through winter. For more on moving tender plants through the cold months, see our guide on how to overwinter plants and containers.
Pruning and shaping
Pruning keeps rosemary bushy, productive, and from getting woody and bare at the base. The best time is after flowering in late spring or early summer; you can also lightly trim through the growing season as you harvest. The critical rule: never cut back into the bare, leafless old wood. Unlike many shrubs, rosemary generally will not resprout from old wood, so always cut within the green, leafy growth, leaving plenty of foliage on each stem. Trim to shape, remove any dead or crossing branches, and pinch growing tips to encourage branching. A light annual prune of no more than a third keeps an upright plant dense and prevents the leggy, open form that old neglected rosemaries develop.
Harvesting
You can harvest rosemary year-round in mild climates, snipping sprigs as needed. Cut 4–6 inch tips of soft, new growth for the best flavor, taking from different parts of the plant so you don’t denude one area — and remember that every harvest is also a light pruning, so cut just above a leafy node to encourage branching. Flavor is strongest just before the plant flowers and in the morning after the dew has dried. Avoid taking more than about a third of the plant at once. Rosemary is one of the few herbs that dries beautifully: hang small bundles in a dry, airy spot, then strip the needles into a jar. The woody stems also make excellent skewers for grilling.
Overwintering
Whether rosemary survives winter outdoors depends entirely on your zone and variety. In zones 8 and warmer, it stays outside as a permanent evergreen shrub. In zone 7, hardy varieties like "Arp" and "Hill Hardy" usually make it, especially in a sheltered, well-drained spot with a winter mulch over the roots — but the danger is as much wet, cold soil as it is cold air. In zone 6 and colder, treat rosemary as a container plant and bring it indoors before the first hard frost. Move it to a cool, very bright spot, reduce watering, and resist the urge to coddle it; the goal is to hold it dormant-ish until spring. Ease it back outside gradually after frost danger passes, reacclimating it to direct sun over a week or two so the foliage doesn’t scorch.
Propagating from cuttings
Rosemary is easy and satisfying to propagate, which is the smart way to hedge against winter losses. In late spring or summer, take 4–6 inch cuttings of softer, non-flowering new growth. Strip the leaves from the lower two-thirds, dip the cut end in rooting hormone (optional but helpful), and insert into a gritty, free-draining mix or even a glass of water. Keep them in bright, indirect light and lightly moist; roots typically form in 2–4 weeks. Once well rooted, pot them up in that gritty mix. Taking a few cuttings each summer means you always have backup plants if a winter takes your main one.
Pests and problems
Healthy, well-drained rosemary has few pests, but stressed or indoor plants attract a few. Powdery mildew — a white dusty film, especially on humid indoor plants with poor air movement — is the most common issue; improve circulation with a fan and avoid wetting the foliage. Spider mites stipple and web the leaves on hot, dry, or stressed indoor plants; rinse the foliage and raise humidity slightly. Aphids and whiteflies occasionally appear on tender new growth and respond to insecticidal soap. The most dangerous "pest" is root rot from overwatering or poor drainage, which shows as yellowing, browning, and sudden dieback — the only cure is prevention through gritty soil and a dry-between-waterings habit.
Rosemary is the cornerstone of a low-water Mediterranean herb garden. Pair it with thyme, oregano, and sage, all of which share its love of sun and lean soil. To round out the planting, see our guides on growing thyme and our full library of herb and plant growing guides.
Frequently Asked Questions
Why does my rosemary keep dying?
The usual culprit is overwatering or poor drainage causing root rot — rosemary wants to dry out between waterings and needs gritty, fast-draining soil. Indoors, the other big killers are too little light and warm, stagnant air. Give it strong sun, a free-draining mix, and water only when the soil is dry.
Can rosemary survive winter outdoors?
It depends on your zone. Most rosemary is hardy to about USDA zone 8; hardy varieties like "Arp" and "Hill Hardy" can survive zone 7 (and sometimes 6) in a sheltered, well-drained spot with mulch. In colder zones, grow it in a pot and bring it indoors before hard frost.
How often should I water rosemary?
Sparingly. Let the soil dry between waterings — established plants in the ground rarely need watering outside of drought. Container plants need more frequent watering since pots dry faster, but still only when the top inch or two is dry. Overwatering kills far more rosemary than underwatering.
How do I prune rosemary without killing it?
Prune after flowering, cutting only within the green, leafy growth — never into bare old wood, which generally won’t resprout. Trim to shape and pinch tips to keep it bushy, removing no more than about a third at once. Regular light pruning prevents the leggy, woody form of neglected plants.
Can I grow rosemary from a cutting?
Yes, and it’s the easiest method. Take 4–6 inch cuttings of soft new growth in spring or summer, strip the lower leaves, optionally dip in rooting hormone, and root them in a gritty mix or water in bright indirect light. Roots form in 2–4 weeks. Seed is slow and unreliable by comparison.