Lily (its members are true lilies) is a kind of herbaceous flowering plants growing from bulbs, which all have large and significant flowers. Lilies are a group of flowering plants, which are very important in culture and literature in many parts of the world. Most species are native to the temperate northern hemisphere, although their range extends to the northern subtropical zone. Many other plants are called "lilies" in general, but they have nothing to do with real lilies.

Lilies are tall, perennial plants with a height of 2 – 6 feet (60 – 180 cm). They form naked or unbound underground bulbs, which are their perennial organs. In some North American species, the base of the bulb develops into a rhizome on which many small bulbs are found. Some species grow stems. Most bulbs are buried deep underground, but a few species form bulbs near the surface of the soil. Many species form stems and roots. With these, the bulbs can grow naturally at a certain depth in the soil. Every year, the new stems will stretch out indefinite roots from the soil above the bulbs. These roots are complementary to the basal roots that develop at the base of the bulb.

The flowers are large, usually fragrant, with many colors, including white, yellow, orange, pink, red and purple. Markers include spots and strokes. These plants bloom at the end of spring or summer. In the raceme or umbel at the top of the stem, six perianths spread or fold back, and their shapes range from funnel-shaped to "Turk hat". Perianth is mutually exclusive, with a nectary at the base of each flower. The ovary is above the attachment point of anther and located at the "upper position". Fruit is a three hole capsule.

The seeds ripen at the end of summer. They exhibit different and sometimes complex germination patterns, many of which are suitable for cool temperate climates.

Naturally, most cool temperate species are deciduous and dormant in winter in their native environment. However, a few species (Candida albicans, Lilium albopictus, Lilium longiflorum) distributed in hot summer and mild winter areas lost their leaves and kept relatively short dormancy state in summer or autumn. They germinated from autumn to winter, forming dwarfs with basic wreaths of leaves. Until they cool enough, the stems begin to elongate in warmer weather.

The basic chromosome number is twelve.

Many species are widely planted in gardens in temperate and subtropical regions. They can also grow as potted plants. Many ornamental hybrids have been developed. They can be used for herb boundaries, woodland and shrub cultivation, and as terrace plants. Some lilies, especially long lilies, form important cut flower crops. These may be forced to be used in specific markets; for example, the Lilium longiflorum, known as the Easter lily, is used for Easter trading.

Lilies usually grow bulbs during dormancy. It's best to plant them facing south (northern hemisphere), slightly inclined, in the sun or part of the shadow, at a depth of 2? Times the height of the bulb (except for the pseudofilament lilies that should be planted on the ground). Most like porous, fertile soil, good drainage is essential. Most species bloom in July or August (northern hemisphere). Some lilies begin to bloom at the end of spring, while others bloom in late summer or early autumn. They have retractable roots that pull plants down to the right depth, so it's better to plant them shallower than deeper. A soil pH of about 6.5 is generally safe. The soil should be well drained and plants must be watered during the growing season. Some plants have strong stems, but those with heavy flower heads may need lofting.