**Rosemary** (now classified as *Salvia rosmarinus*, formerly *Rosmarinus officinalis*) is primarily one species with many cultivars. These vary mainly by **growth habit** (upright vs. trailing/prostrate), size, cold hardiness, foliage and flower color, leaf size, and flavor intensity.
Most garden and culinary rosemary falls into two main groups, with some intermediate mounding or spreading forms. All prefer full sun and well-drained soil; most are hardy in USDA zones 8–10 (or warmer), though a few tolerate colder conditions.
### Upright Varieties
These grow as woody shrubs (typically 3–6+ feet tall), with vertical stems suited to hedges, borders, containers, or heavy culinary harvesting. They generally produce abundant aromatic leaves.
Popular examples include:
- **Tuscan Blue** (or Blue Tuscan) — Vigorous upright form (often 4–6+ feet), large olive-green leaves, dark blue flowers, strong classic flavor. Excellent for cooking, hedges, and warm climates.
- **Arp** — One of the most cold-hardy (survives lower temperatures better than most, often to around –10°F / –23°C with protection). Upright open growth, gray-green narrow leaves, bright blue flowers. Good culinary option for cooler zones.
- **Hill Hardy** (or Madelene Hill) — Another cold-tolerant upright type, somewhat more compact than Arp, with balanced flavor.
- **Barbecue** — Upright with strong flavor/fragrance and long, straight, sturdy stems ideal as skewers. Light blue flowers.
- **Gorizia** — Upright with broader leaves, pale blue/violet flowers, and a pleasant aroma (sometimes noted with ginger notes); good for culinary and ornamental use.
- **Miss Jessopp’s Upright** — Strongly vertical, dense, aromatic; useful for tall hedges or structured planting.
- **Salem** — Neat upright habit, relatively cold-resistant, mild flavor.
- **Spice Islands** — Strong, resinous flavor; upright form good for kitchen use.
- **Albiflorus / Albus** — White-flowered upright forms for ornamental interest.
### Trailing, Prostrate, or Creeping Varieties
These stay low (often under 1–2 feet tall) and spread horizontally or cascade, making them ideal as ground covers, for slopes, retaining walls, hanging baskets, or containers. Leaves are still edible and aromatic, though some are grown more for ornament.
Popular examples include:
- **Prostratus** (Prostrate Group) — Classic low-spreading form that trails well.
- **Huntington Carpet** — Dense, fast-spreading ground cover with pale blue flowers and bright green foliage.
- **Irene**, **Blue Rain**, **Santa Barbara** — Trailing habits suited to cascading over edges or walls; various shades of blue flowers.
### Other Notable Forms
- **Golden or variegated types** (e.g., Golden Rain / Joyce de Baggio / Aureus) — Foliage that turns yellow or golden in cooler seasons for color contrast.
- **Compact/dwarf or mounding** (e.g., Blue Boy, Baby PJ) — Smaller plants good for containers, edging, or limited space.
- **Pink-flowered cultivars** (e.g., Majorca Pink or similar) — Offer different bloom color while retaining typical foliage and scent.
**Note**: Plants called “bog rosemary” (*Andromeda polifolia*) are unrelated and not used as culinary herbs.
### Choosing a Type
- **For cooking** — Upright varieties with larger leaves and strong but balanced flavor (Tuscan Blue, Barbecue, Gorizia, Spice Islands) are often preferred; most rosemaries are edible, though intensity and camphor notes vary.
- **For cold climates** — Prioritize Arp or Hill Hardy; otherwise grow in pots and protect or overwinter indoors.
- **For landscaping** — Match habit to space (upright for structure/hedges; trailing for ground cover or cascades). Flower color (mostly shades of blue, plus white or pink options) and foliage interest add ornamental value.
There are dozens of named cultivars available through nurseries; local climate, intended use (culinary vs. ornamental), and space are the best guides for selection.
How to grow rosemary?
**Rosemary** (*Salvia rosmarinus*, formerly *Rosmarinus officinalis*) is a drought-tolerant Mediterranean evergreen herb that thrives with full sun, excellent drainage, and minimal fuss once established. It is typically hardy outdoors in USDA zones 7–10 (some varieties like ‘Arp’ tolerate zone 6), and is often grown as a container plant or annual in colder areas.
### Ideal Growing Conditions
- **Light**: Full sun — at least 6–8 hours of direct sunlight daily. Indoors, use a south-facing window or supplement with grow lights.
- **Soil**: Light, well-draining, sandy or loamy soil with a pH of about 6.0–7.5 (slightly acidic to neutral/alkaline). Amend heavy clay with coarse sand, grit, or perlite. It prefers lean-to-average fertility rather than rich, moisture-retentive soil.
- **Water**: Allow the top inch or two of soil to dry out between waterings. Overwatering is the most common cause of failure (root rot). Established plants in the ground are quite drought-tolerant; containers need more frequent checks in hot weather.
- **Temperature/Humidity**: Prefers 55–80°F (13–27°C). Moderate humidity; high humidity increases fungal risk. Protect from hard freezes.
- **Fertilizer**: Minimal needs. A light application of balanced fertilizer or compost in spring is usually enough. Excess nitrogen reduces flavor intensity.
### Planting
Plant outdoors in spring after the last frost when soil has warmed (around 60–70°F / 16–21°C). In warmer climates, fall planting also works.
- **In the ground**: Choose a sunny, free-draining site (raised beds help in heavy soil). Space plants 18–36 inches (45–90 cm) apart. Plant so the top of the root ball is level with or slightly above the soil surface.
- **In containers**: Use a pot at least 12 inches (30 cm) wide and deep with drainage holes. Mix potting soil with grit, perlite, or sand (up to ~25%) for drainage. Terra cotta pots help excess moisture evaporate.
### Starting Plants
- **From nursery plants or transplants** (easiest and fastest): Buy healthy starts and plant as above.
- **From cuttings** (recommended for reliability and speed): Take 3–6 inch (8–15 cm) softwood or semi-hardwood cuttings from new, non-flowering growth in late spring or summer. Strip lower leaves, optionally dip in rooting hormone, and insert into a moist, gritty mix (potting soil + sand/perlite). Keep in bright indirect light, warm (around 70°F / 21°C), and humid (cover with a plastic bag or dome, venting daily). Roots typically form in 4–8 weeks.
- **From seed** (slower and lower success rate): Sow indoors 8–12 weeks before the last frost. Germination can take 2–3+ weeks and rates are often modest. Keep moist and warm. Harden off seedlings before transplanting when they are several inches tall.
### Ongoing Care
- **Pruning**: Lightly trim after flowering (late spring/summer) to keep plants compact and bushy. Cut into green leafy growth; avoid hard pruning into old woody stems, which may not regrow. Harvesting sprigs throughout the season also encourages branching. Don’t prune late in fall in cold climates.
- **Mulch**: In colder zones, apply mulch around (not against) the crown after the ground freezes for winter protection. Gravel or grit works well in warmer areas to keep the crown dry.
- **Winter care**: In zones below 7–8, grow in containers and bring indoors to a cool, bright spot before hard frost. Reduce watering. Some gardeners take cuttings in fall to overwinter smaller plants indoors.
- **Pests/Diseases**: Generally resistant. Watch for spider mites, aphids, or whiteflies indoors; root rot from poor drainage is the main threat outdoors. Good air circulation helps.
### Harvesting
Snip young, tender tips as needed once the plant is established (usually several months after planting). Flavor is often best just before flowering. Use fresh, or dry bundles upside-down in a well-ventilated area. Avoid removing more than about one-third of the plant at once.
Rosemary pairs well with other Mediterranean herbs (sage, thyme, lavender) and is often used near paths for fragrance. With proper drainage and sun, it can live for many years and become a productive landscape or kitchen plant. Start with a cutting or nursery plant for the quickest success.
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