The name lily is applied to many plants, but "true lilies" belong to the genus Lilium. There's a great deal of variety when choosing lilies. There are 9 different divisions of lilies and they can be short, tall, swept-back, upright, trumpet, speckled, or blushed in colors from pure white to blood red and almost everything in between. What they all share is a certain elegance of form and sweetness of fragrance, making lilies regal flowers in the garden and as gifts and bouquets for special occasions like weddings and Easter Sunday.
Types of Lilies
Lilies are tall, upright plants with whorls of leaves running the length of the plant and flowers that can be bowl-, bell-, trumpet-shaped or even flat; borne singularly or in groups and facing every which way. They come in almost every color except blue. Most of the true lilies we grow today are hybrids and are classified into nine divisions:
- Division I: Asiatic Hybrids
- Division II: Martagon Hybrids (Turk's Cap)
- Division III: Candidum Hybrid
- Division IV: American Hybrids,
- Division V: Longiflorum Hybrids
- Division VI: Trumpet and Aurelian Hybrids
- Division VII: Oriental Hybrids
- Division VIII: All other Hybrids
- Division IX: All True Species
Of these, the most commonly found and grown are the Asiatic Hybrids (Div. I), the Martagon or Turk's Cap Lily (Div. II), the Trumpet or Aurelian Hybrids (Div. VI) and the Oriental Hybrids (Div. VII). There are also approximately 100 different species of lilies (Div. IX), with more hybridizing being done every year.
- Asiatic lilies are the most commonly grown garden lily. They are among the earliest lilies to bloom and come in the widest range of colors and sizes. The showy blooms face either upward or outward. Asiatic lilies are easy growers and tend to multiply quickly. The shorter varieties, like 'Pixie', are ideal for containers, reaching only about 1 to 2 feet in height. Most Asiatic lilies do not require staking. The fragrance is not great in Asiatic lilies, but they make a great cut flower because of their extremely strong stems. Asiatic lilies root above the bulb, along with the stem, and can be planted deeper than other lilies. This makes them even hardier and easier to grow.
- Oriental lilies are especially popular because of their large bloom size and intense fragrance. 'Casa Blanca', the classic pure white heavenly-scented lily, is an Oriental. Oriental lilies generally do not start blooming until mid- to late summer. These can be some of the tallest lily plants, many reaching 6 feet or more, and benefit from some protection from strong winds.
- Trumpet lilies are so named because their petals are partially fused and extend forward like a trumpet. They also have the distinction of having no spots. Trumpet lilies have a strong fragrance and can grow even taller than Oriental lilies, topping 8 feet. So once again, protection from strong winds is encouraged. Recent hybridizing with Oriental and Asiatic lilies has resulted in a wider range of colors of Trumpet lilies.
- Turk’s cap lily or the Martagon hybrids have petals that face downward with swept-back or reflexed petals, giving them the appearance of a "Turk's Cap". Turk's cap lilies began as woodland hybrids and are better able to handle some shade than other lilies. The flowers are a bit smaller than other divisions and the fragrance is not agreeable to every gardener. They range in height from about 4 to 7 feet and come mostly in shades of burgundy, yellow and orange, many with speckles and spots.
Lilies, True Lilies
- Divisions I and II: USDA Hardiness Zones 3 to 8
Divisions III through IX: USDA Hardiness Zones 4 to 8
Some can also be grown in USDA Zones 9 to 10 if given a period of refrigeration to pre-chill them.
Mature Plant Size
The height of lily plants varies greatly between divisions and even within divisions. Lily plants can be found that grow from about 1 foot tall to over 8 feet tall.
Sun Exposure for Lily Plants
Lilies grow well in full sun to partial shade. (Trumpet lilies need full sun, Turk's Cap prefers partial shade.) Too much shade will cause lily plants to lean towards the sun.
When lilies bloom will be different for each variety. Some begin blooming in late spring and others peak at the end of the season. Generally, the Asiatics are the earliest to bloom, followed by the Oriental and Trumpet hybrids and then the Turk's Caps.
Lily Growing Tips
Lilies are grown from scaly bulbs that are usually planted in the fall. You can purchase plants in the spring, for blooms the first year, but fall-planted bulbs have the advantage of getting their roots well established before the growing season begins.
Lily bulbs like to be planted deeply (3 times their diameter) to keep cool and moist in the ground. However, plant container-grown lilies to the same depth they are in their pots.
Space lily bulbs 10 inches apart to provide adequate air circulation and avoid fungal diseases. Mulch is recommended for lilies to keep the roots cool in summer and to protect them from freezing and thawing in the winter.
Caring for Your Lily Plants
Lilies are early risers in the spring, often poking through the soil before the last frost. Don't worry, they'll survive a bit of cold. Flowering time depends on the species and can be anywhere from late spring through fall. So it is possible to have lilies in bloom all season.
Lilies aren't divided and only species lilies will grow true from seed. Most lilies are propagated by separating either the scales or the bulblets that form around the main bulb. This can be a slow process, taking 2 to 3 years before a new plant will flower.
Deadhead just the flowers or seed pods, not the flower stalks. The stalks and leaves will feed the bulb for next year.
When cutting lilies for bouquets, cut when the buds have not quite fully opened, but are showing their color. This will help them last longer. Do not cut more than 1/3 of the flower stem, so that there is still plenty of foliage to feed the bulb.
Problems When Growing Lilies
- Botrytis: All lilies are prone to botrytis in cool, damp weather. Provide good air circulation.
- Lily mosaic virus: This disease can be prevalent in tiger lilies (Lilium tigrinum), although it does not harm them. However, the virus can be carried by insects to other varieties which will be more affected. Lily mosaic virus can cause distorted, streaked or mottled foliage. It is often recommended that tiger lilies not be planted near other hybrid lilies. Lily mosaic virus is not curable and infected plants should be destroyed.
- Lily leaf beetle: The larvae of the lily leaf beetle can be controlled with neem. If you have a major problem with this beetle, try growing "Black Beauty" lilies, which the adults seem to avoid.
Great Varieties of Lilies to Grow
- 'Connecticut King' (Asiatic): 3 to 4 feet tall, with yellow blooms in early summer.
- 'Casa Blanca' (Oriental): 4 to 5 feet tall, with white blooms in late summer.
- 'Stargazer' (Oriental): 2 to 3 feet tall, with red flowers with dark red spots in peak summer
Using Lilies in Your Garden Design
Lilies look best when allowed to shine by themselves, in large clumps, However, the tall, straight lily plants combine well with other sun lovers like bushy peonies and sword-like iris. Lilies are addictive as cut flowers, so grow extras. Remember to remove the anthers so the pollen doesn't stain you or the petals.