How to Grow Rosemary
Rosmarinus officinalis
Rosemary is an aromatic evergreen herb prized for its needle-like leaves and woody stems. Gardeners cultivate it primarily to enhance culinary dishes with a piney flavor or to create fragrant landscapes that thrive in sunny spots.
📷 Wikimedia CommonsStarting Rosemary: indoors or direct sow?
🏠 Start indoors 8 weeks before your last spring frost, then move the seedlings outside.
Move seedlings outdoors only after all danger of frost has passed and soil temperatures have warmed sufficiently for this tender perennial.
Soil, care & harvest
Prepare well-draining soil with a pH between 6.0 and 7.0, as rosemary struggles in heavy clay. Since this is a tender perennial often started indoors, begin seeds 8 to 12 weeks before your last frost date. Sow them about 1/4 inch deep; germination typically takes 14 to 21 days under warm conditions.
Space plants 18 to 24 inches apart to ensure good air circulation, which is vital for preventing fungal issues. While rosemary requires low water once established, keep the soil moist during initial growth and apply a light mulch to retain moisture without suffocating roots. Feed sparingly if growth seems sluggish.
Watch for spider mites, aphids, and scale insects; maintain airflow to deter powdery mildew and root rot caused by poor drainage. Harvest sprigs after 90 to 120 days from sowing when leaves are fully formed. Snip stems just above leaf nodes to encourage bushy growth without damaging the woody base.
When to Plant Rosemary
Planting windows vary by USDA hardiness zone. Look up yours by ZIP code.
Companion Plants for Rosemary
✓ Good companions
Repels aphids and whiteflies, complementary water and soil requirements
Beans fix nitrogen in soil while rosemary repels bean beetles
Strong scent deters flea beetles and cabbage loopers that attack brassicas
Rosemary repels cabbage moths, cabbage worms, and other brassica pests
Rosemary deters carrot flies while carrots don't compete for nutrients
Shared preference for well-draining soil and full sun, mutual pest deterrence
Similar Mediterranean growing conditions, both deter pests like cabbage worms
Rosemary repels tomato hornworms and whiteflies that damage tomatoes
✗ Keep away from
Rosemary's allelopathic compounds can stunt cucumber growth and development
Rosemary's strong oils and root secretions inhibit lettuce germination and growth
Competition for space and rosemary's allelopathic effects reduce pumpkin yields
Nutrition Facts
Per 100g serving (USDA FoodData Central)
