Multiflora rose (Rosa multiflora) is an ornamental climbing shrub native to East Asia. The specific epithet ‘multiflora’ means ‘many flowers’ and refers to the great number of flowers the plant produces. The flowers are usually white, but some pink varieties can be found. Multiflora rose is considered a noxious weed in certain parts of the world.
I. Appearance and Characteristics
Rosa multiflora (syn. Rosa polyantha) is a species of rose known commonly as multiflora rose, baby rose, Japanese rose, many-flowered rose, seven-sisters rose, Eijitsu rose and rambler rose. It is native to eastern Asia, in China, Japan, and Korea. It should not be confused with Rosa rugosa, which is also known as “Japanese rose”, or with polyantha roses which are garden cultivars derived from hybrids of R. multiflora. It was introduced to North America, where it is regarded as an invasive species.
It is a scrambling shrub climbing over other plants to a height of 3–5 m (9 ft 10 in – 16 ft 5 in), with stout stems with recurved prickles (sometimes absent). The leaves are 5–10 cm (2–4 in) long, with 5–9 leaflets and feathered stipules. The flowers are produced in large corymbs, each flower small, 1.5–4 cm (5⁄8–1+5⁄8 in) diameter, white or pink, borne in early summer. The hips are reddish to purple, 6–8 mm (15⁄64–5⁄16 in) diameter.
Plants of the World Online and Flora of China include the varieties:
- Rosa multiflora var. adenochaeta (Koidz.) Ohwi
- Rosa multiflora var. cathayensis Rehder & E.H.Wilson. Flowers pink, to 4 cm (1+5⁄8 in) diameter.
- Rosa multiflora var. multiflora. Flowers white, 1.5–2 cm (5⁄8–3⁄4 in) diameter.
II. How to Grow and Care
Sunlight
Multiflora rose favors full sun and also can tolerate a half shade environment. In partial shade, it usually only grows leaves and does not bloom. Even if it has flower buds, the flower is neither gorgeous nor fragrant. As a result, it is recommended that gardeners ensure sunlight at least 6 hours per day during the growing season (but not necessarily in winter). In summer, it should be appropriately shaded to prevent overexposure to sunlight.
Temperature
Multiflora rose is widely distributed from cold temperate zones to tropical areas. It likes cool, ventilated environments and is not tolerant of high temperatures. The optimum temperature range is 15 to 26 ℃. Some species can tolerate temperatures as low as -26 ℃ and high temperatures of up to 35 ℃. When the temperature is below 4 ℃ in winter and above 30 ℃ in summer, the plant becomes semi-dormant and has poor growth. The flowers during this period will have a few small, white petals with a dim and lusterless color and are not good-looking at all.
Multiflora rose favors moist conditions but is not resistant to water-logging. It can tolerate moderate drought. Provide more water from budding to flowering, but reduce watering after blooming time. After blooming, wait to water again until the soil is basically dry to avoid any accumulation. Ensure good ventilation and drain excess water during the rainy season to prevent damage to its roots.
Watering
Originating from East Asia, multiflora rose is accustomed to moderate moisture levels and can tolerate short periods of drought. This species thrives in well-drained soil with consistent moisture, displaying a preference for environments that mimic its native habitat’s balance between wet and dry cycles. For optimal health, multiflora rose should be watered once every 1-2 weeks, ensuring the soil has time to dry slightly between watering sessions. Typically grown outdoors due to its vigorous growth habit, multiflora rose benefits greatly from rainwater during its active growing season, which supplements irrigation and contributes to its lush foliage and abundant flowering.
Soil
Multiflora rose can adapt to a variety of soil types and grows best in acidic soil which is fertile, loose, and water-drained. When planting in the garden, you should choose a place on higher terrain with sufficient sunlight, good air ventilation, and slightly acidic soil. Planting in high terrain helps avoid water accumulation in soil. Before planting, deeply loosen the soil and use organic fertilizer as base fertilizer. If planting as a potted plant, use humus-rich and slightly acidic sandy soil.
Fertilizing
For healthy growth, fertilize multiflora rose with balanced nutrition fertilizers. In spring, apply high nitrogen fertilizers to promote lush foliage. Fertilization should be done every 4-6 weeks during the growing season, using the amount recommended on the product label. Benefits include vibrant blooms and robust growth. Over-fertilization harms multiflora rose, so follow guidelines precisely. Adjust feeding with seasonal changes; reduce in fall. Tip: water multiflora rose before and after applying fertilizer to prevent root burn.
Pruning
Multiflora rose has a strong sprouting ability and grows luxuriantly. Without proper, timely pruning, it will attract diseases and pests in hot, humid, insufficiently lit, or poorly ventilated conditions. After the first bloom, the plant should be slightly pruned. Promptly cut off faded flowers and thin, overlapping branches, leaving only young and strong branches. During winter dormancy, careful pruning is recommended.
For vines, keep main branches at 2 to 3 m long and cut off the rest. For bush plants, cut 1.02 cm above full buds, prune the whole plant to 1/3 of its original height, and leave 4-6 thicker branches while ensuring that the overall shape of the plant meets your desired appearance.
Propagation
Originating from East Asia, multiflora rose is recognized for its vigorous growth and innate ability to reproduce. Propagation through cuttings stands out as a practical approach, utilizing semi-hardwood stems. Gardeners should select healthy, disease-free shoots, trim below the node, and subject them to rooting hormone treatment before embedding in well-draining soil. This method encourages successful rooting, enabling effective spread or replenishment of multiflora rose without the intricate care demands of other techniques.
Transplanting
Multiflora rose thrives when transplanted during the prime season of mid-spring to early summer, as it enables healthy root establishment. In an ideal location, seek well-drained soils with full sun exposure. For transplant success, allow ample spacing and gently tease roots apart if needed.
Repotting
Repot multiflora rose in early spring as it gears up for vigorous growth. This climbing shrub thrives when given space; choose a large, sturdy pot to accommodate its extensive root system. Post-repotting, ensure multiflora rose has ample sunlight and water regularly for robust recovery. Repot every 2-3 years to maintain health and vigor, reducing potential stress on the plant.
Pests and Diseases
Keep an eye out for aphids, leafhoppers, glasshouse red spider mite, scale insects, caterpillars, large rose sawfly, rose leaf-rolling sawfly, leaf-cutter bees, black spot, rose rust and rose powdery mildew. Deer and rabbits can also cause damage
III. Uses and Benefits
Rosa multiflora is grown as an ornamental plant and also used as a rootstock for grafted ornamental rose cultivars.
In eastern North America, Rosa multiflora is considered an invasive species. It was originally introduced from Asia as a soil conservation measure, as a natural hedge to border grazing land, and to attract wildlife. It is readily distinguished from American native roses by its large inflorescences, which bear multiple flowers and hips, often more than a dozen, while the American species bear only one or a few on a branch.
In some regions the plant is classified as a noxious weed. In grazing areas, it is generally considered to be a serious pest, though it is considered excellent fodder for goats.
The hips of the plant are edible.
IV. Harvesting and Storage
Multiflora rose produces excellent fresh flowers that can be pruned with sharp scissors as soon as they bloom. It is best to pick flowers in the morning to avoid loss of water through plant transpiration at noon. After picking, it is necessary to trim the base of the branch at a 45° angle to increase the water absorption area. Quickly put the flower into a vase with clean water to avoid water loss.
