How to Care for a Potted Rosemary Bush

Choose a pot suited to growing rosemary plants. Select a glazed ceramic or heavy plastic pot measuring at least 8 inches in diameter. Find one with at least three drainage holes at the base.

Combine 1 part coir, 2 parts potting soil, and 2 parts coarse sand to create a suitable growing medium for the rosemary plant. Drizzle water over the components while stirring, until the growing medium feels moderately moist throughout.

Fill the bottom third of the planter with the growing medium. Settle the root ball of the rosemary plant onto the soil. Add growing medium around the root ball until it is completely covered and sturdy in the planter.

Water the rosemary plant with 2 cups of water to thoroughly saturate the soil. Water with 1 cup of water whenever the top 2 1/2 inches of soil are dry. Reduce water to 1/4 cup during the winter.

Place the potted rosemary where it will receive at least six hours of sunlight each day. Set it near a large window with southerly exposure, or on a bright, sunny porch.

Move the potted rosemary plant to a cool, bright location for the winter, such as inside an unheated room with large windows. Keep temperatures around 50 degrees Fahrenheit during the winter.

Hard prune the plant in winter around mid February. Prune each individual stem to half its length with pruning shears. Use the clippings for cooking, or dry them for use later.

Move the potted rosemary plant outside for a few weeks in spring. Feed the plant 1 tbsp. fish emulsion diluted in 2 cups of water while it is outside. Let the soil dry thoroughly after you feed the plant, to eliminate any unpleasant fishy smell.

Replace the soil in the rosemary's pot every couple of years to encourage vigorous growth. Remove most of the soil from around the roots, and repot with a fresh batch of the growing medium.