What are the three varieties of bush roses?
Large flowered bush (used to be hybrid tea): upright growth, large flowers carried on one stem or in small clusters, repeat flowering.
Cluster flowered (used to be floribunda): Upright growth, bear smaller flowers carried on large clusters or trusses, repeat flowering and often flower for longer periods.
Dwarf cluster (used to be patio): Similar growth pattern to cluster flowered but on a smaller scale.
What are the five varieties of shrub roses?
Species rose: Wild roses that have been cultivated
Old roses: A group of roses including Gallica, Moss, Damask and Rugosa from which modern shrub roses have been developed.
Modern shrub: General heading for roses that don’t fall into other categories, for example English roses.
Groundcover roses: Roses with a low spreading habit. Can be vigorous.
Climbers and ramblers: Climbers have stiff upright growth with large flowers, can be repeat flowering. Ramblers are more flexible with smaller flowers carried in clusters, once a season.
List and explain some uses for roses in garden design.
Traditional rose gardens: Large gardens often had a separate rose garden, often surrounded by a low growing hedge (perhaps of lavender).
Mixed border: Roses mixed in with other plants, for example annuals and herbaceous perennials.
Clothing walls, pergolas, other structures: Climbers and ramblers can create vertical interest or conceal unattractive sights.
Hedging: Rosa rugosa and other shrub roses can be planted to create an informal hedge.
In containers: Dwarf varieties can be grown in pots on a patio.
What are the two ways to buy roses and when?
Barerooted in autumn and winter or containerised at any time.
Describe the siting/planting of roses in a garden.
- An open, sunny site with some shelter from the wind
- Soil ideally well-drained clay loam of pH 6.5, but tolerant of a range of conditions
- With the graft union 2.5cm below the soil level to prevent suckering
- 40cm from the wall if planted at the base of a wall.
Explain the formative pruning of a rose bush.
Prune back hard to an outward facing bud 10-15cm from the base after planting in autumn.
Prune climbing roses to encourage up to six strong canes trained towards the wall.
Explain the maintenance of roses.
Feeding: an annual application of a fertiliser which should have a balance of NPK plus trace elements. Applied in spring as a granular top dressing at rate recommended on label.
Dead heading: remove spent flowers to encourage more flowering (expect species that produce hips, if you want hips).
Removing suckers: remove any shoots emerging from the rootstock to stop it depleting the grafted part of the plant.
Pruning: Prune in early spring to remove dead, diseases or damaged wood and to open up the frame of the plant. Prune back by a quarter in autumn to prevent wind rock.
Explain the pruning of bush roses.
- Remove any dead, diseased or damaged wood
- Remove any inward or crossing branches to create a nice open vase shape and improve ventilation and prevent disease
- Remove older canes, leaving 6 to 8 healthy young canes
- Prune canes back to approximately 30cm above ground level, just above an outward-facing bud.
Explain the pruning of a climbing rose.
- Modern climbing roses flower on this season’s wood
- Prune in spring (although older varieties prune in autumn)
- Establish a permanent framework of canes, trained along a wall or fence as horizontal as possible to break apical dominance
- Once the framework is established, cut the laterals back to 3 buds from the main cane and remove 1 or 2 of the older canes from the ground level in spring.
Explain the pruning of a shrub rose.
- Shrub roses can flower both on last season’s wood and this season’s, depending on their group
- In autumn the lateral shoots should be shortened by roughly half and some canes should be removed to ground level to encourage new vigorous growth
- It is important to retain the height of the rose as excessive pruning will result in a plant that is all leaf and no flower.
Name three large flowered roses.
- Rosa ‘Peace’ Yellow and pink repeat flowering
- Rosa ‘Silver Anniversary’ White repeat flowering
- Rosa ‘Ruby Wedding’ Pale crimson repeat flowering.
Name three cluster flowered roses.
- Rosa ‘Iceberg’ White flowers
- Rosa ‘Gold Bunny’ Yellow flowers
- Rosa ‘Queen Elizabeth’ Pink flowers
- Rosa ‘Mountbatten’ Yellow flowers.
Name four pests and two diseases affecting roses.
- Black spot: fungal black spots appear on stems. Soil borne. Use sulphur based fungicide.
- Powdery mildew. White ashy powder fungal growth on leaves and leaf petioles and flower buds
- Rust: orange or black pustules on leaves or stems. Fungal.
- Aphids. Sucking insects in green or black appear on buds and other soft tissue, weakening plant.
