Agapanthus is a landscape staple in warm-winter regions, and it's no wonder why. This easy-to-grow perennial produces colorful globes of blue or white trumpet-shape flowers in summer and fall. Its evergreen strappy leaves add texture to beds, borders, and containers. Agapanthus blooms best in a spot where it gets full sun and has moist, well-drained soil. Divide it every three to four years to keep clumps healthy and vigorous. If you live in a cool-winter area, you can overwinter agapanthus in containers by bringing the pots to a cool (around 40 degrees F) spot and watering them only once a month or so. In spring, move the containers back outdoors after all danger of frost has passed. Potted agapanthus is said to bloom best when slightly root-bound.