Rosemary (Rosmarinus officinalis) is a wonderfully fragrant and beautiful evergreen plant. This tasty herb is not difficult to grow, and once established it will live a long time if you take proper care of it. Rosemary plants need a lot of sun and do not flourish in cold climates, which is why they are often grown in containers that can be moved indoors. Set a pot of rosemary on your kitchen windowsill and use it to flavor your recipes.
Plant or place your rosemary plant (if it is in a container) in a sunny location. Rosemary, like most other herbs, needs 5 to 6 hours of sunlight per day in order to thrive.
Grow rosemary in a well-ventilated area. It needs to be exposed to circulating air to prevent the growth of fungi. An open window is ideal for a container plant. If the weather is too cold for that, set a fan near the plant for an hour a day. Outdoor plants should not be overly sheltered by larger plants that might block breezes.
Water rosemary sparingly. The herb has fragile roots that quickly succumb to root rot if left in soggy soil. Most problems with rosemary are due to over-watering. Do not water your rosemary plant until the soil is completely dry and has been for 2 or 3 days.
Fertilize rosemary once a month with an all-purpose, balanced (10-10-10) fertilizer.
Transplant container-grown rosemary once a year, or more frequently if it grows too large for its pot. To transplant, unpot the rosemary plant and trim an inch off the bottom of the roots, then place it in a new pot. Make sure the pot has drainage holes and fill the bottom inch or so with sand or pebbles.