Rosemary: Care, Size & Growing Zones
About Rosemary
‘Rosemary’ is a wonderfully-fragrant, evergreen, herb that features rich, green needle-like foliage and small, exquisite, pale blue flowers that bloom in late spring. Long-appreciated by chefs world-wide as an essential flavoring for meats, vegetables, and seafoods, this beautiful herb is believed to promote sleep, alleviate headaches, and treat skin conditions, as well. Available in an attractively-rounded, erect form, which is ideal for sunny borders or hedges; another variety of gracefully-trailing ‘Prostrate Rosemary’ is available with the ability to cascade from stone walls, flow over the rims of decorative containers, or cover the ground. This charming herb is well-adapted within USDA hardiness zones 7-10 and can reach a typical height and spread of two to six feet. Native to the Mediterranean, ‘Rosemary, or ‘Salvia rosmarinus officinalis’ flourishes in coastal settings. In fact, the genus “rosmarinus” translates from Latin to “dew of the sea” in reference to the plant’s love of its native seaside habitat. The genus name, ‘Salvia,’ or “salveo” means to “save or heal,” and the species name, “officinalis” refers to “medicinal uses.” This flavorful, healing, and aromatic herb enhances the landscape while at the same time providing nutrition and shelter to a multitude of beneficial pollinators and wildlife.Propagation & Planting
‘Rosemary’ thrives in loamy or sandy, slightly-acidic, well-drained soil. This plant requires a minimum of six or more hours of direct sunlight daily. Purchased nursery transplants can be planted in spring, after the last frost, at the same soil depth they were in the previous container. Transplants should be spaced two to four feet from other plants to permit adequate air circulation. The addition of compost is beneficial at the time of planting. ‘Rosemary’ can be propagated from several-inch-long cuttings, taken in the fall, then pressed into moist growing medium. Established roots may also be divided and transplanted. The plant can be layered by lowering a branch to the ground and anchoring it until new roots develop. While this plant can be propagated by seed, germination is slow and less reliable than other methods.
Plant Care
‘Rosemary’ thrives in well-drained, evenly moist, but never soggy or water-logged soil. The plant should be watered every one or two weeks in the heat of summer, allowing the top few inches of the soil to dry between each watering. ‘Rosemary’ suffers when winter temperatures drop below thirty degrees Fahrenheit and may need to be covered or brought indoors for protection.
Fertilize
‘Rosemary’ does not require fertilizer, other than the addition of compost at the time of planting, and can be harmed from over-fertilization.
Prune
Prune as needed to maintain plant shape during spring and summer, up to 4-6 weeks before first frost. Use sharp, clean shears to avoid ragged cuts that could leave plant exposed to disease. If looking to reduce overall size of plant, cut back 1/3 of plant, wait 2-3 months and then cut back additional 1/3, as desired. If you desire a bushier plant, cut off the top 1-2 inches to encourage branch to split.
Pests & Disease
This plant prefers poor, dry, rocky, infertile soil, and excellent soil drainage is essential for the prevention of fungal disease. Aphids or mealybugs can be treated with insecticidal soap, if necessary, making sure to read and carefully follow the directions on the product label.
Attracts
Resistances
Tolerances
Rosemary FAQs
How much sun and water does rosemary need?
Rosemary needs full sun (6+ hours) and tolerates part sun. It needs little water and grows best in well-drained sandy loam. It is hardy in USDA zones 7A to 10B.
When should I prune rosemary?
Prune as needed during spring and summer to keep its shape, stopping 4 to 6 weeks before the first frost. To shrink a large plant, cut back one third, wait 2 to 3 months, then cut back another third if needed. Use sharp, clean shears.
Does rosemary need fertilizer?
No. Apart from compost added at planting time, rosemary does not need fertilizer, and too much fertilizer can harm it.
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