Lilium superbum (Turk's cap lily) — Upright unbranched stems from a scaly bulb

Overview

Lilium superbum is a upright unbranched stems from a scaly bulb bulb in the genus Lilium, part of the Liliaceae family, with deciduous; narrow lance-shaped leaves, scattered or in whorls up the stem foliage. It typically grows around 2.4 m tall. Lilium superbum grows best in full sun with the roots in shade; some species prefer dappled light, and tolerates deep humus-rich loam and or loam-based compost in pots soils and neutral to acid and though madonna and trumpet lilies tolerate lime pH. Its UK hardiness is rated H4-H6. It is native to E United States.

About

Lilium superbum is a tall bulbous lily with upright, unbranched stems arising from a scaly bulb, reaching around 2.4 m. Leaves are deciduous, narrow and lance-shaped, arranged either scattered or in whorls up the stem. It flowers from June to August. Bulbs are ornamental and toxic if eaten; handle with gloves and note that it is toxic to cats.

Wikipedia contributors, CC BY-SA 4.0 — Lilium superbum

About the genus

Lilium is a genus of herbaceous flowering plants growing from bulbs, all with large and often prominent flowers. Lilies are a group of flowering plants which are important in culture and literature in much of the world. Most species are native to the Northern Hemisphere and their range is temperate climates and extends into the subtropics.

Wikipedia contributors, "Lilium", CC BY-SA 4.0 — Lilium

In the garden

Lilium superbum is a North American bulbous lily of the Liliaceae, native to the eastern United States. It produces single upright stems from a scaly bulb and carries narrow lance-shaped leaves that are shed after the season. Flowering occurs in the UK from June to August, when the blooms stand well above the foliage. Plant it where the crown and stems receive full sun while the bulbs remain cool and shaded; a thick mulch or a low ground cover will help protect the roots. Use deep, humus-rich loam in the ground or a loam-based compost in large pots, and avoid positions that stay stagnant wet since bulbs will rot in such conditions. pH should be neutral to acid; note that some lily groups tolerate lime, but Lilium superbum prefers neutral to acid soil. Choose a south, west or east-facing, sheltered spot to reduce wind damage. Hardiness is H4–H6 (average to very hardy), so the lily will survive standard UK winters in sheltered sites. It suits the back of a sunny herbaceous border or large containers where you can keep the root zone cool and moist but well drained. Because the bulb and plant tissue are poisonous, always wear gloves when handling and keep cats away; the green-centred flowers can help confirm identification in summer.

Growing conditions

Best soil and position for Lilium

Sunlight: Full sun with the roots in shade; some species prefer dappled light
Soil type: Deep humus-rich loam, or loam-based compost in pots
Soil pH: Neutral to acid, though Madonna and trumpet lilies tolerate lime
Soil moisture: Moist but sharply drained - bulbs rot in stagnant wet
Aspect: South, west or east facing
Exposure: Sheltered
UK hardiness: H4-H6

Plant details

Lilium superbum size, habit and characteristics

Plant type: Bulb
Habit: Upright unbranched stems from a scaly bulb
Foliage: Deciduous; narrow lance-shaped leaves, scattered or in whorls up the stem
Height: 2.4 m
Native to: E United States
Toxicity: Ornamental bulbs - not to be eaten. Wear gloves and other protective equipment when handling. TOXIC to pets if eaten (cats) - see the HTA guide to potentially harmful plants for further information and useful contact numbers

Care notes

Pruning and caring for Lilium superbum

Cultivation: Plant bulbs deeply, at roughly three times their own depth, on a layer of grit so water drains away from the scales; the exception is Lilium candidum, which sits just below the surface. Feed while in growth and let the stem die down naturally afterwards so the bulb can rebuild. Container growing gives the sharp drainage most lilies want and makes lily beetle far easier to police.
Pruning: Remove faded flowers to stop seed forming, but leave the stem and foliage until it has yellowed completely, then cut to the base.
Propagation: Detach offset bulbs or individual scales when dormant and grow them on in a cold frame. Species can be raised from seed, though flowering may take three to five years.
Pest resistance: Scarlet lily beetle is the serious pest and will strip a plant if unchecked - adults and larvae both need removing on sight. Slugs damage emerging shoots.
Disease resistance: Botrytis marks the foliage in wet summers. Virus, spread by aphids, causes streaked and distorted growth and cannot be cured.

Frequently asked questions

How do I grow Lilium superbum?

Plant bulbs deeply, at roughly three times their own depth, on a layer of grit so water drains away from the scales; the exception is Lilium candidum, which sits just below the surface. Feed while in growth and let the stem die down naturally afterwards so the bulb can rebuild. Container growing gives the sharp drainage most lilies want and makes lily beetle far easier to police.

Where is the best place to plant Lilium superbum?

Lilium superbum prefers full sun with the roots in shade; some species prefer dappled light. It suits sheltered positions.

What soil does Lilium superbum need?

Lilium superbum grows best in deep humus-rich loam and or loam-based compost in pots soil. It prefers neutral to acid and though madonna and trumpet lilies tolerate lime soil. Aim for soil that stays moist but sharply drained - bulbs rot in stagnant wet.

How do I prune Lilium superbum?

Remove faded flowers to stop seed forming, but leave the stem and foliage until it has yellowed completely, then cut to the base.

How big does Lilium superbum grow?

Lilium superbum reaches a height of 2.4 m.

Is Lilium superbum hardy in the UK?

Lilium superbum has an RHS hardiness rating of H4, meaning it is hardy through an average UK winter, tolerating -10 to -5°C.

How do I propagate Lilium superbum?

Detach offset bulbs or individual scales when dormant and grow them on in a cold frame. Species can be raised from seed, though flowering may take three to five years.

Is Lilium superbum toxic?

Ornamental bulbs - not to be eaten. Wear gloves and other protective equipment when handling. TOXIC to pets if eaten (cats) - see the HTA guide to potentially harmful plants for further information and useful contact numbers.

More in the Lilium genus

Browse all Lilium →