Last updated on July 3rd, 2026 at 04:20 pm
How to Care for Lily of the Nile Plants (Agapanthus)
Lily of the Nile (Agapanthus) is a beautiful perennial that thrives in regions with mild temperatures, higher humidity, and regular rainfall. Its long, arching, grassy leaves resemble monkey grass, creating an attractive clump of foliage even when the plant is not in bloom.
Although agapanthus grows well in the Desert Southwest, it requires more frequent watering than many other landscape plants. It is not considered drought tolerant and performs best when the soil is kept evenly moist during the growing season. A properly installed drip irrigation system works well. During the hottest part of summer, watering for about 15 to 20 minutes every other day is generally sufficient for established plants, although the schedule may need to be adjusted depending on your soil type, weather conditions, and the age of the plant.
In early summer, sturdy flower stalks rise 1 to 2 feet above the foliage and produce large clusters of brilliant blue flowers that often last for several weeks. After the blooms fade, simply cut the flower stalk back to the base to encourage the plant to direct its energy into producing additional flowers and healthy new growth.
Agapanthus is widely available at local garden centers and nurseries. You can purchase plants already growing in containers or as dormant rhizomes that can be planted directly in the garden.
Agapanthus is a clump-forming perennial that naturally increases in size each year. In late fall or winter, after the foliage has died back, you can trim the leaves to keep the plant looking neat. The underground rhizomes can be divided to create new plants, but it is best to wait until the danger of frost has passed in late winter or early spring before dividing them. During the winter months, water occasionally to keep the rhizomes from drying out completely. With proper care, your agapanthus will reward you with another spectacular display of flowers each summer.
Where to place the Lily of the Nile Plant
They like full sun but will do nicely in partial shade. Place in the background of your garden with smaller perennials/annuals in the foreground.  They like to be watered often, especially in and around the Southwest area. You can plant them in containers, but they will do much better in the ground. Furthermore, the plant grows rapidly and will get root-bound quickly in a container.
Problems with the Lily of the Nile Plant
Slugs and snails are one big problem, so it’s best to keep an eye out for these pests. Many gardeners who have lots of snails are usually overwatering, or the plant is in too much shade,
Use Diatomaceous earth to keep these pests at bay. Diatomaceous earth is crushed-up seashells and will shred hard-shell insects and snails when they pass through. It is an organic product and will not harm pets or people.
Snails love beer. You can pour a can of beer into a pan and leave it near the plants. The slugs and snails will dive in and drown. Many folks have tried this method, with about half saying it works and the other half saying they are wasting beer!
Mealybugs and Aphids will attack this plant; spraying with insecticidal soaps will normally work. Soaps will work, but it will take several applications before you get results.
Neem oil will help keep snails away but will not kill them; however, it will kill Mealybugs and Aphids if applied correctly. Neem oil is organic, but again, it needs to be applied several times before it works.
Agapanthus plants are susceptible to powdery mildew, which is a fungus that produces a white powdery substance on their leaves. Caused by overwatering and too much shade. The best way to cure this fungus is to cut back about 1/4 of the way down, then spray with a fungicide that contains copper or use Neem oil spray. Remember to clean your pruners before using them on other plants.
What to Feed Agapanthus Plants
Feed these plants during the spring growing season, typically around late April or May. You will get more blooms with a fertilizer high in phosphorus. It is normally the middle number on most fertilizers. Learn more about Fertilizers here: What is Fertilizer?
USDA zone 7-11
It is considered an Evergreen in USDA zones 8-11.
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Paul Guzman is a lifelong Southwest gardener and gardening writer with decades of experience helping homeowners grow beautiful landscapes in the desert Southwest. He writes for Guzman’s Garden Centers in Las Cruces, New Mexico, with contributing expertise from Gary Guzman, owner of Guzman’s Garden Centers. If you have any questions or enjoyed this post, feel free to share your thoughts in the comments below.
