Delphinium 'Mrs Newton Lees'

RHS Plant Profile

delphinium 'Mrs Newton Lees'

Herbaceous Perennial

A deciduous, herbaceous perennial that reaches approximately 1.5m in height when in flower. It forms an even mound of fresh to dark green, incised leaves and flower stems of lilac blue flowers with a black centre, in summer

Position

Full sun

Soil Types

Chalk, Loam, Sand

Max Height

1.5-2.5 metres

Max Spread

0.5-1 metres

Size

Time to Maturity: 1–2 years
Max Spread: 0.5-1 metres
Max Height: 1.5-2.5 metres

Growing Conditions

Chalk Loam Sand

Moisture: Moist but well–drained or Well–drained
pH: Alkaline or Neutral or Acid

Position

Full sun

Aspect: South–facing or West–facing or East–facing
Exposure: Sheltered
Hardiness

Hardiness Ratings

All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets

H1A: under glass all year (>15C)
H1B: can be grown outside in the summer (10 - 15)
H1C: can be grown outside in the summer (5 - 10)
H2: tolerant of low temperatures, but not surviving being frozen (1 to 5)
H3: hardy in coastal and relatively mild parts of the UK (-5 to 1)
H4: hardy through most of the UK (-10 to -5)
H5: hardy in most places throughout the UK even in severe winters (-15 to -10)
H6: hardy in all of UK and northern Europe (-20 to -15)
H7: hardy in the severest European continental climates (< -20): H5

Colour & Scent

Season	Stem	Flower	Foliage	Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family: Ranunculaceae
Native to GB/Ireland: No
Foliage: Deciduous
Habit: Columnar upright, Clump forming
Potentially harmful: Humans/Pets: Harmful if eaten. Wear gloves and other protective equipment when handling. For further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants
Genus: Delphinium can be annuals, biennials or perennials, with palmately lobed basal leaves and showy bowl-shaped flowers in spikes, racemes or panicles
Name Status: Accepted

How to Grow

Cultivation

Grow in fertile, well-drained soil in full sun. Shelter from strong winds and provide support (see staking perennials). Divide every 2-5 years to maintain vigour. See staking perennials and delphinium cultivation for further advice

Propagation

Propagate by division or by basal softwood cuttings in spring

Suggested planting locations and garden types

City and courtyard gardens
Cottage and informal garden
Wildlife gardens
Flower borders and beds
Wall side borders

Pruning

Deadhead spent flower spikes back to fresh flowering side shoots and cut back to ground level in late autumn.

Pests

May be susceptible to aphids, earwigs, delphinium leaf miner, delphinium moth caterpillars, slugs, snails and caterpillars

Diseases

May be susceptible to Powdery mildews, delphinium black blotch, crown rot and viruses