Helianthemum 'Saint John's College Yellow'

RHS Plant Profile
rock rose 'Saint John's College Yellow'

Save a plant

Where do you want to save Helianthemum 'Saint John's College Yellow'?

Plants I own
Wishlist
Go to My Plants

Synonyms

Helianthemum nummularium 'St John's College Yellow'

Shrubs Alpine Rockery
Buy this from Plant Nurseries
1 Suppliers

A low growing, spreading evergreen shrub with linear, silvery-green leaves. Small, bright yellow flowers are produced continuously from late spring to mid summer

Position

Full sun

Soil Types

Chalk, Loam, Sand

Max Height

0.1-0.5 metres

Max Spread

0.1-0.5 metres

Size

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

Growing Conditions

Chalk Loam Sand
Moisture
Well–drained
pH
Alkaline or Neutral

Position

Full sun
Aspect
South–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)
H4

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Cistaceae
Native to GB/Ireland
No
Foliage
Evergreen
Habit
Bushy, Spreading branched
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, neutral to alkaline, well-drained soil in full sun. Will not tolerate waterlogging. May benefit from protection in cold winters

Propagation

Propagate by softwood cuttings in late spring or early summer

Suggested planting locations and garden types

  • Coastal
  • Cottage and informal garden
  • Gravel garden
  • Rock garden
  • Banks and slopes
  • Flower borders and beds
  • Ground cover

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