R2111 6.6 Ten alpine and rock garden plants

Question 1

Aethionema grandiflorum AGM

Answer 1

https://www.rhs.org.uk/search?query=Aethionema%C2%A0grandiflorum

Details: evergreen sub-shrub of rounded habit. Leaves narrow, blue-green. Flowers small, pink, in compact sprays at shoot tips. Fruit a small, flat capsule April to June.

Cultivation: Grow in fertile, well-drained, alkaline soil in full sun. Will tolerate poor, acid soils although growth will be more compact.

Suggested planting locations and garden types:

Coastal, Gravel garden, Rock garden, Cottage and informal garden, Mediterranean climate plants, Flower borders and beds, Wall side borders

H 15–30 cm S 30–45 cm Ultimate H 2–3 years

Question 2

Androsace lanuginosa

Answer 2

Details: evergreen perennial forming a mat to 45cm wide, composed of loose rosettes of silky, grey-green, ovate leaves. Umbels of bright lilac-pink flowers 8-12mm wide on stalks to 10cm open in mid summer

Cultivation: Grow in a scree bed, in vertical crevices in rock or in moist but gritty well-drained soil

Suggested planting locations and garden types: Rock garden, Cottage and informal garden, Gravel garden, Patio and container plants, Banks and slopes, Ground cover

H up to 10 cm S 10–50 cm Time to ultimate H 2–5 years

Question 3

Aubrieta ‘Aureovariegata’

Answer 3

Mat-forming evergreen perennials with small leaves and short racemes of 4-petalled flowers in shades of pink and purple in spring

Question 4

Campanula carpatica

Answer 4

A clump-forming perennial to 30cm, with long-stalked, rounded leaves and solitary, violet-blue or white, open-bell-shaped flowers to 3cm in width

Full sun/partial shade
All faces
Sand, Chalk, Loam
H 10–50 cm S 10–50 cm Time to H 2–5 years

• Softening the edges of a sunny, raised bed or rockery
• A useful little perennial for filling in gaps

Question 5

Corydalis solida subsp. solida ‘George Baker’

Answer 5

A tuberous herbaceous perennial to 25cm, with a tuberous root and grey-green, divided foliage. Tubular, deep brick-red flowers are borne in an erect raceme

Full sun
South, West or East
Well-drained
Sand, Chalk, Loam
H 10–50 cm S 10–50 cm Time to H 2–5 years

Flower magnificently in spring, and then rapidly die down and disappear – so they are great interplanted with things that display themselves later in the season.

Question 6

Dianthus alpinus

Answer 6

Mat-forming hardy perennial with dark green foliage and solitary, pale-spotted, deep pink to cerise flowers 4cm wide, in spring, on stalks 2-10cm tall; tends to be short-lived

Full sun
South, West or East
Well-drained
Sand, Chalk, Loam
Alkaline, Neutral
H 10 cm S 10 cm Time to H 2–5 years

Question 7

Dodecatheon pulchellum

Answer 7

Herbaceous perennial to 30cm in height, with a rosette of lance-shaped leaves to 20cm in length, and umbels of deep cerise to rosy-purple flowers 2cm in length

May to July

Full/partial shade
Sheltered
Clay, Loam
Acid, Neutral
H 20 cm S 20 cm Time to H 2–5 years

• The perfect addition to a woodland or rock garden
• A perfect plant for showing off in a terracotta pot or pan

Question 8

Dryas octopetala

Answer 8

A wide mat to 10cm in height, of small, shiny, oak-like leaves with white undersides. Flowers opening in late spring and early summer are 4cm in width, with about eight oblong petals, followed by silky fruiting heads

Full/partial shade
Well-drained
Chalk, Sand, Loam
H up to 10 cm S 50–100 cm Time to H 5–10 years

• A very desirable plant for the rock garden
• Looks fabulous in pots and is neat enough for a trough or sink

Question 9

Geranium subcaulescens ‘Splendens’

Answer 9

A compact evergreen clump of rounded, dark grey-green leaves and vivid reddish-purple flowers 2.5cm wide in late spring and early summer

Full sun/ partial shade
H 10 cm S 10–50 cm Time to H 2–5 years

• Position at the front of a border or even planted in pots

Question 10

Lewisia cotyledon

Answer 10

A rosette-forming evergreen perennial with fleshy, strap-shaped leaves. Abundant, funnel-shaped purplish-pink, orange, yellow or white flowers 1.5-2.5cm in width are borne in open sprays on stems to 20cm

Partial shade
Sand, Loam,
Acid, Neutral
H 10–50 cm S 10–50 cm Time to H 2–5 years

• A perfect choice for rockeries as well as containers and ground cover, as they are fairly tolerant of dry conditions
• Good for scree