Rosemary bushes thrive easily with minimal maintenance and can live for up to 15 years. They are ideal for gardens and landscapes because they can be grown in the ground or in a pot, planted to spill out over plant boxes, or be shaped as topiaries once they grow large. Rosemary is a common herb in the kitchen, so households who grow rosemary will most likely use a lot of it. It is important to prune rosemary in order to control its growth, usually in the early spring or late fall.
Use sharp pruning scissors to carefully trim off any soft, new growth from the rosemary branches to use for cooking or to dry out as a dried herb.
Prune back with pruning shears any straggling stems that are growing in a direction away from the rest of the plant or that are intertwining and crowding out parts of the plant.
Focus on the bottom area of the rosemary bush around the base of the trunk, and trim back about 4 inches from the tips of the branches for full-grown plants (plants that are at least 1 foot tall). For the younger plants, trim back no more than 2 inches.
Make sure the bottom of the rosemary bush is even all the way around, repeating Step 3.
Continue to focus upward on the rosemary bush, now at the mid-section. Prune back with the pruning scissors about 1/2 inch farther back than the bottom branches. This will shape your rosemary bush.
Continue this process to the top of the rosemary bush, trimming it back slightly more then the section before it.
Continue to clip soft, new stems as they grow to gather for herbs and to maintain the shape of the rosemary bush.