Rosemary is often grown as a topiary. Plants can be shaped or growth controlled by frequent tip-pinching when plants are small. Older plants can be pruned lightly to desired size. Allowing a plant to become slightly pot-bound will encourage flowering. In addition, plants grown from seed may not have the same desirable characteristics as selected cultivars.
Cuttings taken from established plants is the best means of propagation.
Once the root system is established, plant cuttings in pots or outside in a sunny location. For drying, cut sprigs or branches before the plant flowers. Hang bundles upside down in an airy place. When dry, you can leave the sprigs whole or strip the leaves from the stem, and store in an airtight container. Rosemary generally has few pest problems, although it can be attacked by aphids, spider mites, mealybugs or scales.