Many species are widely grown in the garden in
temperate,
sub-tropical and
tropical regions. Numerous ornamental
hybrids have been developed. They are used in herbaceous borders, woodland and shrub plantings, and as patio plants. Some lilies, especially
Lilium longiflorum, form important
cut flower crops or potted plants. These are forced to flower outside of the normal flowering season for particular markets; for instance,
Lilium longiflorum for the Easter trade, when it may be called the Easter lily. Lilies are usually planted as bulbs in the dormant season. They are best planted in a south-facing (northern hemisphere), slightly sloping aspect, in sun or part shade, at a depth 2½ times the height of the bulb (except
Lilium candidum which should be planted at the surface). Most prefer a porous, loamy soil, and good drainage is essential. Most species bloom in July or August (northern hemisphere). The flowering periods of certain lily species begin in late spring, while others bloom in late summer or early autumn. They have contractile roots which pull the plant down to the correct depth, therefore it is better to plant them too shallowly than too deep. A
soil pH of around 6.5 is generally safe. Most grow best in well-drained soils, and plants are watered during the growing season. Some species and cultivars have strong wiry stems, but those with heavy flower heads are staked to stay upright.
Awards The following lily species and
cultivars currently hold the
Royal Horticultural Society's
Award of Garden Merit (confirmed 2017): • African Queen Group (VI-/a) 2002 H6 • 'Casa Blanca' (VIIb/b-c) 1993 H6 • 'Fata Morgana' (Ia/b) 2002 H6 • 'Garden Party' (VIIb/b) 2002 H6 • Golden Splendor Group (VIb-c/a) •
Lilium henryi (IXc/d) 1993 H6 •
Lilium mackliniae (IXc/a) 2012 H5 •
Lilium martagon – Turk's cap lily (IXc/d) •
Lilium pardalinum – leopard lily (IXc/d) • Pink Perfection Group (VIb/a) •
Lilium regale – regal lily, king's lily (IXb/a)
Classification of garden forms Numerous forms, mostly hybrids, are grown for the garden. They vary according to the species and interspecific hybrids that they derived from, and are classified in the following broad groups:
Asiatic hybrids (Division I) File:Lilium canadense.JPG File:Dwarf Asian Lily Tiny Dessert (closeup).jpg File:Lilium %27Navona%272.jpg File:Lily Festival 2009 Neepawa Manitoba Canada %2816%29.JPG File:Lilium Cappuccino.jpg File:Lilium Dimension.JPG : These are derived from hybrids between species in
Lilium section Sinomartagon. : They are derived from central and East Asian species and interspecific hybrids, including
Lilium amabile,
Lilium bulbiferum,
Lilium callosum,
Lilium cernuum,
Lilium concolor,
Lilium dauricum,
Lilium davidii,
Lilium × hollandicum,
Lilium lancifolium (syn.
Lilium tigrinum),
Lilium lankongense,
Lilium leichtlinii,
Lilium × maculatum,
Lilium pumilum,
Lilium × scottiae,
Lilium wardii and
Lilium wilsonii. : These are plants with medium-sized, upright or outward facing flowers, mostly unscented. There are various cultivars such as Lilium 'Cappuccino', Lilium 'Dimension', Lilium 'Little Kiss' and
Lilium 'Navona'. • Dwarf (Patio, Border) varieties are much shorter, c.36–61 cm in height and were designed for containers. They often bear the cultivar name 'Tiny', such as the 'Lily Looks' series, e.g. 'Tiny Padhye', 'Tiny Dessert'.
Martagon hybrids (Division II) File:Lilium %27Claude Shride%27 2013 013.JPG File:Lilium %27Kalna Karalis%27 2013 015.JPG File:Lilium %27Manitoba Fox%27 007.JPG File:Lilium %27Mrs R.O.Backhouse%27 (cropped).jpg File:Lilium %27Slate%27s Morning%27.jpg File:Lilium, Hare Hill, Cheshire 2c.jpg :These are based on
Lilium dalhansonii,
Lilium hansonii,
Lilium martagon,
Lilium medeoloides, and
Lilium tsingtauense. :The flowers are nodding, Turk's cap style (with the petals strongly recurved).
Candidum (Euro-Caucasian) hybrids (Division III) File:Lilium x testaceum.jpg : This includes mostly European species:
Lilium candidum,
Lilium chalcedonicum,
Lilium kesselringianum,
Lilium monadelphum,
Lilium pomponium,
Lilium pyrenaicum and
Lilium × testaceum.
American hybrids (Division IV) : These are mostly taller growing forms, originally derived from
Lilium bolanderi,
Lilium × burbankii,
Lilium canadense,
Lilium columbianum,
Lilium grayi,
Lilium humboldtii,
Lilium kelleyanum,
Lilium kelloggii,
Lilium maritimum,
Lilium michauxii,
Lilium michiganense,
Lilium occidentale,
Lilium × pardaboldtii,
Lilium pardalinum,
Lilium parryi,
Lilium parvum,
Lilium philadelphicum,
Lilium pitkinense,
Lilium superbum,
Lilium ollmeri,
Lilium washingtonianum, and
Lilium wigginsii. :Many are clump-forming perennials with rhizomatous rootstocks.
Longiflorum hybrids (Division V) : These are cultivated forms of this species and its subspecies. :They are most important as plants for
cut flowers, and are less often grown in the garden than other hybrids.
Trumpet lilies (Division VI), including Aurelian hybrids (with L. henryi) File:Lilium x African Queen.jpg File:Lilium %27Fanfare%27.jpg File:Lilium Pink Perfection1f.UME.jpg File:Lilium x Dresdener Romance.jpg File:Lilium x aurelianense1MTFL.jpg : This group includes hybrids of many Asiatic species and their interspecific hybrids, including
Lilium × aurelianense,
Lilium brownii,
Lilium × centigale,
Lilium henryi,
Lilium × imperiale,
Lilium × kewense,
Lilium leucanthum,
Lilium regale,
Lilium rosthornii,
Lilium sargentiae,
Lilium sulphureum and
Lilium × sulphurgale. :The flowers are trumpet shaped, facing outward or somewhat downward, and tend to be strongly fragrant, often especially night-fragrant.
Oriental hybrids (Division VII) File:Oriental hybrid1 (cropped).jpg File:Smithsoniangardens1.jpg File:Lilium Dizzy.jpg File:Lilium x Universe.jpg File:Lilium Golden Stargazer.jpg File:Lilium %27Marco Polo%27 Flower 2580px.jpg : These are based on hybrids within
Lilium section Archelirion, • Flower aspect: :*a up-facing :*b out-facing :*c down-facing • Flower form: :*a trumpet-shaped :*b bowl-shaped :*c flat (or with tepal tips recurved) :*d tepals strongly recurved (with the Turk's cap form as the ultimate state) Many newer commercial varieties are developed by using new technologies such as ovary culture and embryo rescue.
Pests and diseases , UK
Aphids may infest plants.
Leatherjackets feed on the roots.
Larvae of the
Scarlet lily beetle can cause serious damage to the stems and leaves. The scarlet beetle lays its eggs and completes its life cycle only on true lilies (
Lilium) and fritillaries (
Fritillaria). Oriental, rubrum, tiger and trumpet lilies as well as Oriental trumpets (orienpets) and Turk's cap lilies and native North American
Lilium species are all vulnerable, but the beetle prefers some types over others. The beetle could also be having an effect on native Canadian species and some rare and endangered species found in northeastern North America. Daylilies (
Hemerocallis, not true lilies) are excluded from this category. Plants can suffer from damage caused by mice, deer and squirrels. Slugs, snails and millipedes attack seedlings, leaves and flowers. Brown spots on damp leaves may signal an infection of
Botrytis elliptica, also known as Lily blight, lily fire, and botrytis leaf blight. Various viral diseases can cause mottling of leaves and stunting of growth, including lily curl stripe, ringspot, and lily rosette virus.
Propagation and growth Lilies can be propagated in several ways; • by division of the bulbs • by growing-on
bulbils which are
adventitious bulbs formed on the stem • by scaling, for which whole scales are detached from the bulb and planted to form a new bulb • by seed; there are many
seed germination patterns, which can be complex • by
micropropagation techniques (which include
tissue culture); commercial quantities of lilies are often propagated
in vitro and then planted out to grow into plants large enough to sell. A highly efficient technique for multiple shoot and propagule formation was given by Yadav et al., in 2013. Plant grow regulators (PGRs) are used to limit the height of lilies, especially those sold as potted plants. Commonly used
chemicals include ancymidol, fluprimidol, paclobutrazol, and uni-conazole, all of which are applied to the foliage to slow the biosynthesis of
gibberellins, a class of
plant hormones responsible for stem growth. ==Research==