Rosa multiflora var. cathayensis is a robust, sprawling shrub characterized by its abundant clusters of small, fragrant flowers that bloom in a variety of hues. Its arching stems are adorned with sharp thorns and compound leaves, which signal its hardiness and ability to thrive in various conditions. This variant’s vigorous growth habit makes it both a resilient wild specimen and a potential invader in garden settings.
I. Appearance and Characteristics
The stem of rosa multiflora var. cathayensis is stiff and robust, exhibiting a dark green hue. It is characterized by numerous prickles, which are sharp and serve as a protective feature. The stem’s texture is rough to the touch due to these prickles. Typically, it has a moderate thickness of about 0.2 to 0.4 inches (5 to 10 mm). The branching pattern is irregular, contributing to its dense and bushy appearance. This stems’ notable toughness makes it easily distinguishable.
The leaves of rosa multiflora var. cathayensis are compound and green, consisting of 7-9 ovate leaflets. Each leaflet measures about 1-2 inches (2.5-5 cm) in length and features serrated margins. The undersides of the leaflets typically have a layer of fine hairs. The leaflets are arranged in an opposite manner along the rachis, which aids in distinguishing the plant. The overall foliage texture is slightly coarse due to the serrations and hairiness beneath.
The flowers of rosa multiflora var. cathayensis are delicate and single with a light pink hue. Each cluster bears numerous blooms, each measuring roughly 1.5 inches (3.8 cm) wide. The flowers are composed of five petals, arranged symmetrically, and emit a mild, pleasant fragrance. Their blooming period typically occurs in late spring to early summer, contributing to their charm and aesthetic allure. These features, including the soft pink color and fragrant nature, are key for identifying rosa multiflora var. cathayensis’s flowers.
The fruit of rosa multiflora var. cathayensis manifests as small rose hips with a distinctive orangish red to brown hue. Each hip measures approximately 1/4 inch (6.35 mm) in diameter, a diminutive size that characterizes these fruits. The texture of the hips is typically firm to the touch, and they contain the seeds of rosa multiflora var. cathayensis. These rose hips are an identifying feature of the plant, typically developing after the flowering period and persisting through the colder months, providing a splash of color against the bleak winter landscape.
II. How to Grow and Care
Sunlight
Rosa multiflora var. cathayensis 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
Rosa multiflora var. cathayensis 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.
Rosa multiflora var. cathayensis 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
Rosa multiflora var. cathayensis favors moist but not water-logged conditions, so it’s important to keep the soil well-drained whether it’s planted in the ground or potted. When growing outdoors, it can be watered when the soil surface is slightly dry (except for in winter) with no fixed watering frequency. Keep the soil moist, as drought will reduce the number of flowers.
In drought, the plant needs to be watered every 2-3 days. Pay attention to drainage and avoid water-logging during the rainy season. Winter is its dormant period, so it’s okay to stop watering then. The plant is not tolerant of water-logging; its roots easily rot. Avoid water accumulation when watering, and also avoid splashing water onto the leaves to prevent disease.
Potted rosa multiflora var. cathayensis can be watered every 2 days during the growing season except for winter. Only water the plant when the soil surface is slightly dry. In high-temperature seasons, the evaporation of water increases, and the plant is in a weak and semi-dormant period. To prevent it from drying out, water it twice a day in the morning and at night. Additionally, avoid too much exposure to sunlight.
It’s recommended to water potted plants until excess water seeps out from the bottom of the container. Remember to drain the standing water, or place a saucer with pebbles under the pot to allow excess water to flow out easily. During the dormancy period in winter, it should be watered less often. Only water often enough to prevent the soil from becoming extremely dry. Rosa multiflora var. cathayensis needs to be watered more from budding to flowering, and the amount and frequency of watering should be reduced after flowering.
Soil
Rosa multiflora var. cathayensis 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
Rosa multiflora var. cathayensis favors fertile soil, so it’s best to apply fertilizer several times during the growing season, but only in small amounts each time. In the spring and summer, you can use liquid fertilizer twice a month and use slow-release fertilizer every two months. Add more nutrients for more lush plants and flowers. A slow-release organic fertilizer can be used in winter so the new shoot and buds in next year’s bloom will be lush; these flowers will be large and gorgeous.
If rosa multiflora var. cathayensis is to be used for fresh-cut flowers, fertilize them 1-2 times a week during the florescence. Pay attention to the cultivation of branches with flowers. Cut off flower buds from weak branches of the plant to concentrate nutrients in the stronger ones. Additionally, a sprinkling of Mycorrhizal fungi (which is also sold as Root Grow) at the base of the plant will allow the beneficial fungi to form a symbiotic relationship with the root system, helping it to absorb nutrients and water.
Planting Instructions
If planting potted rosa multiflora var. cathayensis in your garden, it’s best to find a suitable site with adequate sunlight, fertile soil, good drainage, and preferably a place that hasn’t been planted with any roses before. A field that previously grew roses may increase the probability of infection. Transplanting can be done in all seasons except winter.
First, dig a pit that is twice as big as the flower pot. Add a small amount of base fertilizer to the pit, and place the root system or root ball into the pit so that the root crown (where the aboveground part and the underground part connect) is at or slightly higher than the surface of the soil. Backfill and slowly compact the soil. A layer of organic mulch can be used to cover the soil surface for heat preservation of roots and also reduce the growth of weeds. Water thoroughly after transplanting and water often in the first week to avoid wilting caused by a lack of water.
If transplanting rosa multiflora var. cathayensis from one part of the garden to another, do it in fall to avoid the cold of winter. Water the plants three days before transplanting; this makes it easy to dig up and retain the root balls. Then, trim off the overlong branches and excessive leaves, leaving 3-4 branches per plant to reduce excessive consumption of nutrients and ensure its survival. Prune any unhealthy roots left after being dug up.
If a bare-root rose cannot be immediately planted after purchase, it can simply be placed into a pit and covered with soil. If it has already gone without water for some time, it’s better to soak its roots in water for half an hour before planting to help it recover. It is recommended to plant bare-root roses in gardens in the fall.
Pruning
Rosa multiflora var. cathayensis 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
Rosa multiflora var. cathayensis can be propagated by grafting. Multiflora rose (Rosa multiflora) is often used as rootstock for grafting. Generally, grafting is carried out from the end of summer to the beginning of autumn, and the grafting part is as close to the ground as possible.
Cut a T-shaped cut on the outer skin of the rootstock with a knife on one side of the stem and branch, then select a bud from the middle of a well-developed branch in the same year, cut the bud with bark, insert it into the T-shaped cut, bind it with plastic film, and place it in proper shade. It can usually be untied 15 days after grafting, and will germinate and survive after 30 days.
You can also select a branch that has not yet developed a leaf bud as a scion if the thickness of the scion is more similar to that of the rootstock. Cut a 2 cm deep cut on the rootstock longitudinally, insert the scion into the cut, and then fasten it with plastic film. The incision will heal after about 10 days.
Rosa multiflora var. cathayensis can also propagate by division. It can be planted deeper and filled with soil to the roots so that new roots can grow at the bottom of each branch. In the early spring or late autumn, the whole plant can be dug out with soil to be divided into ramets. Select a stem with 1-2 branches and some fibrous roots, and then separate it from the whole plant and plant it in a basin or garden. At the same time, prune the branches on the ground to reduce the evaporation of water and improve the survival rate of transplanting.
Cutting propagation, another useful way to propagate rosa multiflora var. cathayensis is generally carried out in spring and autumn. Branches with 3-4 buds can be cut off to use. The substrate for cutting can be a mix of river sand, rice chaff ash, or vermiculite, etc. Insert the branches into the substrate, shade it properly, and spray to maintain humidity. The branches will take root 20-30 days after cutting, and the survival rate is 70-80%.
If the branches are dipped in rooting powder and then inserted into the substrate, the survival rate will be higher. Additionally, the cuttings can be immersed in water for cutting; the cutting temperature is 20 to 25 ℃, and new roots will grow after 20 days.
III. Harvesting and Storage
Rosa multiflora var. cathayensis 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.