Rosa Royal William ('Korzaun') (HT)

Synonyms

Rosa 'Korzaun'

Roses Shrubs

Buy this from Plant Nurseries
8 Suppliers

A compact, free-flowering rose about 75cm tall, with healthy, dark green foliage, and bearing fragrant, shapely, high-centred, deep red, fully double blooms opening from pointed buds, almost continously in flower from summer to autumn

Position

Full sun

Soil Types

Chalk, Clay, Loam, Sand

Max Height

0.5-1 metres

Max Spread

0.5-1 metres

Size

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

Growing Conditions

Chalk Clay Loam Sand

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

Position

Full sun

Aspect: West–facing or South–facing or East–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

Fragrance Flower

Season	Stem	Flower	Foliage	Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family: Rosaceae
Native to GB/Ireland: No
Foliage: Deciduous
Habit: Bushy
Potentially harmful: Fruit are ornamental - not to be eaten. Wear gloves and other protective equipment when handling. Pets: Fruit are ornamental - not to be eaten - see the HTA guide to potentially harmful plants for further information and useful contact numbers
Genus: Rosa can be deciduous or semi-evergreen shrubs or scrambling climbers, with usually thorny stems bearing compound pinnate leaves and solitary or clustered flowers. Flowers may be followed by showy red or purple fruits in some varieties.
Name Status: Trade
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: Hybrid Tea, or Large-flowered bush roses are upright, thorny shrubs with large, usually glossy leaves and large, double often fragrant flowers that may be solitary or in threes

How to Grow

Cultivation

Grow in full sun with fertile, humus-rich, moist but well-drained soil. For best flowering apply a balanced fertiliser and mulch in late winter or early spring and a balanced fertiliser again in early summer. Suits container cultivation, see rose cultivation This plant was included in the RHS Rosa (rose) red-flowered trial 2021-2024 https://www.rhs.org.uk/plants/trials-awards/plant-trial-results/red-roses

Propagation

Propagate by softwood cuttings in early to mid spring, hardwood cuttings in late summer to autumn or by chip budding in summer

Suggested planting locations and garden types

Cottage and informal garden
Patio and container plants
City and courtyard gardens
Cut flowers
Flower borders and beds

Pruning

Pruning group 15 (floribunda and hybrid tea roses)

Pests

May be susceptible to aphids, rose leafhopper, glasshouse red spider mite, scale insects, caterpillars, large rose sawfly, rose slugworm sawfly and rose leaf-rolling sawfly. Deer and rabbits can cause damage

Diseases

May be susceptible to rose black spot, rose rust, replant disease, rose dieback, and rose powdery mildew and sometimes honey fungus. May also be susceptible to disorders rose blindness and flower balling