Blue flowers offer a serene and captivating beauty, providing a refreshing contrast to common reds, yellows, and pinks. They can transform outdoor spaces into calming retreats or vibrant focal points, evoking feelings of peace and natural elegance.
Understanding Blue Lilies
The term “blue lily” can be misleading, as true Lilium species rarely produce genuinely blue flowers. Instead, this common name refers to diverse plants with stunning blue blooms, often resembling lilies in form or growth habit. Understanding these distinctions is important for successful cultivation.
The Blue Lotus (Nymphaea caerulea), or Egyptian Blue Water Lily, is a prominent aquatic perennial from northern and tropical Africa. It features star-shaped, light blue flowers that float on the water surface, with round leaves connected to submerged rhizomes. Nymphaea violacea, another water lily from northern Australia, also has blue-violet blooms.
Agapanthus, known as Lily of the Nile or African Lily, is a terrestrial perennial from South Africa. Despite its common names, it is not a true lily but part of the Amaryllidaceae family. It produces clusters of blue, lavender, or white bell-shaped flowers on tall stalks above strap-like leaves.
Ixia, or African Corn Lily, is a cormous perennial from South Africa. While available in many colors, some varieties display a metallic blue-green hue with a violet center. These plants have star-shaped, six-petaled flowers on wiry stems above sword-like leaves.
Essential Growing Conditions
Successful cultivation requires specific environmental conditions, varying for aquatic and terrestrial types. Most blue-flowering plants thrive in full sun (6-8 hours daily). Nymphaea caerulea prefers full sun but tolerates part shade. Terrestrial varieties like Agapanthus and Ixia also flourish in full to afternoon sun, though partial shade may reduce blooms.
Soil requirements vary. Nymphaea caerulea rhizomes need heavy, muddy soil in containers submerged in 9-16 inches of still water (above 70°F/21°C). Terrestrial types like Agapanthus and Ixia require well-drained soil. Agapanthus benefits from organic matter, while Ixia prefers sandy to humus-rich loam with a pH of 6.5-7.0.
Watering practices are distinct. Aquatic lilies need consistent water levels. Terrestrial varieties require regular watering during the growing season. Established Agapanthus are drought-tolerant, needing water only during dry spells. Ixia needs even moisture during growth but dry conditions during dormancy to prevent rot.
Temperature and hardiness zones are crucial. Nymphaea caerulea (Zones 10-12) needs water above 70°F (21°C) and must be overwintered indoors in colder climates. Agapanthus (Zones 7-11, depending on type) may need lifting or indoor storage in colder regions. Ixia (Zones 8-10) corms should be lifted and stored in frost-free conditions in colder areas.
Care and Maintenance
Ongoing care ensures robust growth and flowering. Fertilization is important: Nymphaea caerulea needs monthly aquatic plant tablets. Agapanthus may benefit from a complete fertilizer in winter or spring, especially in containers. Ixia benefits from all-purpose fertilizer during growth, or dilute balanced fertilizer every two weeks for container plants.
Pruning and deadheading encourage blooms and health. Deadhead Agapanthus to prevent seeding and promote flowering; remove yellowing leaves. For water lilies, remove dead or damaged foliage and weak stems twice yearly (spring and fall) for vigorous growth.
Pest and disease management is generally straightforward. Nymphaea caerulea may get aphids; inspect and remove pests. Agapanthus is mostly pest and disease-free, but botrytis fungus can occur in humid areas. Ixia is also generally pest and disease-free, though new shoots may attract snails and slugs.
Winterizing protects less hardy varieties in colder climates. Nymphaea caerulea (outside Zones 10-12) must be brought indoors before frost; rhizomes can be stored, or plants overwintered in a greenhouse or aquarium. Deciduous Agapanthus can be mulched; containerized evergreens moved indoors (55-60°F/12-15°C). Ixia corms, if not hardy, should be dug up after foliage dies and stored dry.
Symbolism and Cultural Significance
Beyond horticulture, “blue lilies,” especially the Blue Lotus (Nymphaea caerulea), hold profound symbolism. Revered as a symbol of creation, rebirth, and the sun, ancient Egyptians associated it with the sun god Ra and the sun’s daily journey due to its opening and closing cycle.
It also symbolizes purity, spiritual enlightenment, and wisdom. In Indian culture, “Padma” represents spiritual awakening and divine beauty, linked to Hindu and Buddhist deities. Ancient Egyptians used it in ceremonial rituals for tranquility and heightened awareness, and for perfumes.
Agapanthus, or Lily of the Nile, symbolizes love, affection, and beauty, its Greek name meaning “flower of love.” It also represents purity, fertility, and rebirth, making it popular for weddings. Some traditions used its roots for health and fertility.
Ixia, though less recognized, is associated with happiness, joy, and optimism in various cultures, its vibrant blooms adding cheer to gardens.