Dianthus 'John Sandall' (b) | carnation 'John Sandall'

RHS 1999

Herbaceous Perennial

An evergreen perennial to around 60cm in height, with greyish foliage and single white flowers 5cm wide, with broad white petals edged and flecked with deep cherry-red

Position

Full sun

Soil Types

Chalk, Loam, Sand

Max Height

0.5-1 metres

Max Spread

0.1-0.5 metres

Size

Time to Maturity: 2–5 years
Max Spread: 0.1-0.5 metres
Max Height: 0.5-1 metres

Growing Conditions

Chalk Loam Sand

Moisture: Well–drained
pH: Alkaline or Neutral

Position

Full sun

Aspect: South–facing or East–facing or West–facing
Exposure: Exposed or 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): H6

Colour & Scent

Season	Stem	Flower	Foliage	Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family: Caryophyllaceae
Native to GB/Ireland: No
Foliage: Evergreen
Habit: Bushy
Potentially harmful: Humans/Pets: Skin allergenwear gloves and other protective equipment when handling. For further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants
Genus: Dianthus can be annuals, evergreen perennials or subshrubs with narrow, often greyish leaves and showy flowers that are frequently fragrant
Name Status: Accepted
Horticultural Group

Horticultural Classification Codes

Horticultural Classification Codes are often given to genera which have a large number of species or cultivars. They are used to categorise cultivated plants based on specific, shared characteristics such as shape, colour, size or flowering time, and can be displayed as letters or numbers

For example:
Dahlia ‘Sunset Kate (Sin) = Single flower
Rosa ‘Marigold’ (HT) = Hybrid Tea: Border carnations are hardy evergreen perennials with linear leaves and erect stems bearing fully double flowers to 8cm across in mid-summer, sometimes clove-scented

How to Grow

Cultivation

Grow in a well-drained, neutral to alkaline soil in full sun. Prefers a soil enriched with well-rotted manure or garden compost and an application of a balanced fertiliser in spring

Propagation

Propagate by softwood cuttings of non-flowering shoots in summer or by layering after flowering

Suggested planting locations and garden types

Cottage and informal garden
Flower borders and beds

Pruning

Deadhead regularly to prolong flowering

Pests

May be susceptible to slugs and aphids

Diseases

May be susceptible to powdery mildews, a rust, a virus and fusarium wilt