Helianthemum 'Sudbury Gem'

RHS Plant Profile
rock rose 'Sudbury Gem'
Shrubs Alpine Rockery

A compact, evergreen shrub to 20cm high forming a mat of small, grey-green leaves and bearing single, deep pink, saucer-shaped flowers with yellow eyes from late spring into summer

Position

Full sun

Soil Types

Chalk, Clay, Loam, Sand

Max Height

0.1-0.5 metres

Max Spread

0-0.1 metre

Size

Time to Maturity
2–5 years
Max Spread
0-0.1 metre
Max Height
0.1-0.5 metres

Growing Conditions

Chalk Clay Loam Sand
Moisture
Well–drained
pH
Alkaline or Neutral

Position

Full sun
Aspect
South–facing or West–facing or East–facing
Exposure
Exposed or Sheltered
Hardiness
H4

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Cistaceae
Native to GB/Ireland
No
Foliage
Evergreen
Habit
Matforming
Genus
Helianthemum are bushy or spreading evergreen shrubs with small paired leaves and saucer-shaped flowers borne in short racemes in spring and early summer
Name Status
Accepted

How to Grow

Cultivation

Grow in moderately fertile well-drained neutral to alkaline soil in full sun. This plant was included in the RHS Helianthemum (rock rose) trial 2024-2026 https://www.rhs.org.uk/plants/trials-awards/ongoing-plant-trials/helianthemum

Propagation

Propagate by softwood cuttings in late spring or early summer

Suggested planting locations and garden types

  • City and courtyard gardens
  • Coastal
  • Cottage and informal garden
  • Gravel garden
  • Rock garden
  • Low Maintenance
  • Flower borders and beds
  • Banks and slopes

Pruning

Pruning group 10 after flowering

Pests

Generally pest-free

Diseases

May be susceptible to honey fungus in gardens where it is present but insufficient data to determine degree of susceptibility