How to Plant and Grow Rosemary

Known for its scent and flavor, rosemary can be planted as an herb or a garden ornamental. This perennial evergreen shrub, hardy in Zones 8-10, can be grown as an annual in other climates. It grows quickly and can get very big.

The best time to harvest your rosemary is in the morning, just after any dew has evaporated. You can snip stems throughout the growing season to use fresh, or cut a bunch to dry in the fall. To use rosemary, strip the needlelike leaves from the stems and chop before adding to dishes. Store fresh rosemary up to one week in the refrigerator by placing the stems in a plastic bag with a damp paper towel.

Pulverize the dry leaves before adding them to dishes, herb blends, or sauces so the aromatic oils are released, and they're easier to chew. Rosemary's texture and flavor vary throughout the season—leaves are tender in the spring, with fewer aromatic oils. By late summer, the foliage packs a more potent flavor.

Where to Plant Rosemary

Because of their Mediterranean heritage, these plants thrive in hot and dry weather. Grow rosemary near paths and walkways to release its fragrance as you brush past it. Plant it where there's lots of sunshine, away from any taller plants that could block the light.

The needle-like texture of its leaves makes rosemary an interesting addition to mixed borders among plants with broad or strappy leaves.

How and When to Plant Rosemary

Plant rosemary in the spring, once the weather has warmed up after the final frost. Plants should be 2 to 3 feet apart, and seeds planted with just a dusting of soil on them. To plant a potted rosemary, dig a hole about the same width and depth as the planting container. Remove the plant and loosen the roots a bit from the root ball before placing in the hole. Backfill with soil, tamp lightly, and water well.

If you plan to grow it indoors, rosemary can be planted anytime. It may need supplemental light if there's not enough bright light coming through windows. You'll know rosemary needs light when it gets leggy.

Rosemary Care Tips

Rosemary is an easy herb to care for and fungus-resistant in the right environment.

Light

Rosemary thrives in full sun. Part sun drastically increases the likelihood of problems with fungi.

Soil and Water

Rosemary needs well-drained, slightly acidic-to-neutral soil to survive. It will slowly suffer in heavy and moist clays, especially during winter. Water regularly, but don't overwater since rosemary doesn't thrive in soggy soil. When topsoil is dry, it's time for watering. Once plants are established, they're drought-tolerant.

When growing potted rosemary indoors, it's important to get the watering cadence just right. The soil should be moist but not water-logged.

Temperature and Humidity

Dry, hot air is best for rosemary. Humidity can create problems with fungi, especially if plants are too close together. They won't survive cold weather (under 30ºF) but can take the heat. The best temperatures for rosemary are between 55ºF and 85ºF.

Fertilizer

Before planting, add a few inches of aged compost or other rich organic matter into the soil. Fertilize rosemary in spring and summer with an organic, high-nitrogen fertilizer. For the amount to use, follow product label directions. Avoid chemical fertilizers, especially if you plan to cook with cuttings from your rosemary plant.

Pruning

Prune rosemary to your preferred size and style, including topiary designs. Pruning will make the plant bushier. However, don't prune more than a third of the plant at a time because it can cause stress.

Potting and Repotting Rosemary

If you're growing rosemary as an annual or a potted plant, try growing it indoors. This can be challenging since rosemary likes it hot and dry with plenty of sun. So in the home, make sure plants are in full sun if possible—southern exposure is best. Container plants need a well-draining potting mix that's light. Since rosemary grows substantially, it needs repotting at least every year. You'll know it's time to repot when the lower leaves begin to yellow. The best time to repot is in the spring.

Pests and Problems

Poor airflow and high humidity are significant contributors to powdery mildew and can cause loss of flavor in rosemary. Additionally, watch out for spider mites, mealy bugs, whitefly, and aphids. If you spot any of these pests, use insecticidal soap to wash them away.

Rosemary is deer-resistant.

How to Propagate Rosemary

The best way to propagate rosemary is with cuttings. Rosemary seeds are difficult to germinate, and the seeds need to be of excellent quality, as do the growing conditions, for seeds to grow.

Propagate by cutting a branch from an existing plant. Strip the bottom of the branch of its leaves and dip the end of the cutting in rooting hormone. Add to a container with soilless potting mix and place it in a bright spot. Keep soil moist, and the branch should have roots in a few weeks and be ready for planting. You can pull gently on the branch to see if there are roots.

Types of Rosemary

Arp Rosemary

Rosmarinus officinalis 'Arp' forms a sturdy upright shrub three to five feet tall and two to three feet wide. Zones 6–10

'Tuscan Blue' Rosemary

Rosmarinus officinalis 'Tuscan Blue' is one of the best rosemary varieties for topiaries. It develops dense blue-green foliage that's easily sheared into any shape. It's highly fragrant, and has many uses in the kitchen. It grows four feet tall. It grows as an annual except in Zones 8–10.

Trailing Rosemary

Rosmarinus officinalis 'Prostratus' has a trailing growth habit that looks great cascading over a retaining wall or trailing down a raised bed. It is also called creeping rosemary or prostrate rosemary, and it makes an effective groundcover. It grows 18–24 inches tall, spreads four to eight feet wide, and bears light-blue flowers. Zones 8–10

'Roman Beauty' Rosemary

Rosmarinus officinalis 'Roman Beauty' is a compact, slow grower with a semitrailing form, growing just 12–16 inches tall and spreading 18–24 inches wide. It grows more upright than trailing rosemary, but still creates a cascading effect in the landscape or in container gardens. It has violet-blue flowers and fragrant gray-green foliage. Zones 8–10

'Gorizia' Rosemary

Rosmarinus officinalis 'Gorizia' is noted for its exceptionally wide leaves, often twice as broad as common rosemary. It grows four feet tall and wide, and it bears clusters of light blue flowers from late winter through summer. Zones 8–10

Golden Variegated Rosemary

Rosmarinus officinalis 'Aureus' has green needlelike leaves with gold flecks. This rosemary is an upright grower that reaches two feet tall and spreads equally wide. It has pale blue flowers in spring. Zones 8–10

'Majorca Pink' Rosemary

Rosmarinus officinalis 'Majorca Pink' has unusual pinkish-lavender blooms in spring with repeat blooms in summer. It's an upright plant growing four feet tall and two to four feet wide. Zones 7–10

'Benenden Blue' Rosemary

Undemanding Rosmarinus officinalis ’Benenden Blue’ is an excellent choice for poor but well-drained soils. Its namesake blue flowers appear in late spring and summer. It grows 2-3 feet tall and wide in zones 4-11.

Barbecue Rosemary

Rosmarinus officinalis 'Barbecue' is a selection developed for its excellent flavor and aroma. It can grow four feet tall and will develop beautiful blue blooms. It grows as an annual, except in Zones 8–10.

Companion Plants for Rosemary

Flowering Kale

The scent of rosemary keeps pests away from flowering kale and other brassica. Its bright colors stand out against rosemary's simple greens. Zones 2-11

Green Beans

Rosemary's stronger aroma hides the scent of green beans and other beans from Mexican bean beatles, which are deadly to bean plants. Zones 3-10

Lavender

Lavender and rosemary have the same requirements for soil and water, and their scents complement each other. Zones 5-0

Garden Plans for Rosemary

Drought-Tolerant Garden Plan

This informal mixed garden bed features drought-tolerant trees, evergreen shrubs, perennials, and annuals.

Classic Herb Garden Plan

Ensure your kitchen is always stocked with fresh herbs with this classic herb garden plan, where ten kinds of herbs surround a decorative sundial in a 6-foot-diameter bed.

Colorful Herb Garden Plan

Get an herb garden that dazzles with this colorful plan, where a 3x8-foot border features foliage with purple, green, and golden hues—including variegated leaves.