Detailed Explanation of Cultivation Techniques and Management Methods for Medicinal Roses
The rose is a perennial herbaceous plant of the Rosaceae family. Medicinal roses are mainly used medicinally for their flower buds, while the leaves and roots can also be used medicinally. The cultivation and management techniques are as follows:
Land Preparation and Planting
Land preparation: For rose cultivation, it is advisable to choose sandy soil with deep soil layers, loose soil structure, a low groundwater table, good drainage and rich organic matter. Apply 3000 kg/667 sq m of compost, deep plough 20-30 cm, then level the land and make beds.
Transplanting: Dig holes at a row spacing of 1.5-2 m and a plant spacing of 0.6-0.8 m, with a hole depth of 40-50 cm and a hole diameter of 50-60 cm, or dig planting trenches 0.6-0.8 m deep and wide. Apply an appropriate amount of farmyard manure, cover with 5 cm of fine soil, plant the grafted rose seedlings in the holes, spread the root system out evenly in all directions, firm the soil, and water thoroughly to settle the roots. Grafted seedlings require rootstock with a well-developed root system, a stem diameter of 3-4 mm and a plant height of 30 cm. Planting time: spring planting is carried out in early spring before the roses begin to sprout; autumn planting is carried out from October to December.
Varieties: Medicinal red rose, abundant-flowering rose, double-petalled rose or purple-branch rose, etc. may be selected.
Soil, Fertilizer and Water Management
Hilling soil around the roots: After the roses shed their leaves, hill up 4-8 cm of soil around the base of the roses to promote root growth.
Deep ploughing to improve the soil: After 2-3 years of planting, carry out this after harvest in combination with fertilization, doing it year by year. From the outer edge of the planting hole, follow the row direction, with a trench depth of 40-50 cm and a width of 50-60 cm; when deep ploughing, injure the large roots of the plants as little as possible.
Intertillage and weeding: Carry out 4-5 times each year to keep the soil loose. The depth of intertillage is generally 10-15 cm; do not damage the roots.
Rational fertilization: After the autumn harvest, open a ring-shaped trench around the plants for topdressing, mainly with farmyard manure, 2000-3000 kg/667 sq m, adding an appropriate amount of cake fertilizer and calcium fertilizer, mix well and apply, then carry out one winter irrigation. When the rose buds begin to sprout in early spring, apply quick-acting fertilizer mainly of nitrogen combined with nitrogen and phosphorus, such as urea and diammonium phosphate, at 10 kg/667 sq m. During the rose budding and flowering stage, apply 10 kg/667 sq m of quick-acting compound fertilizer as topdressing. If the soil is dry when fertilizing, irrigate thoroughly once.
Irrigation and drainage: Drought will reduce flower yield and lower flower quality, so attention should be paid to irrigation in the dry season; in the rainy season, prevent waterlogging and drain water to prevent root rot.
Pruning and Training
Pruning is divided into winter-spring pruning and post-flowering pruning. Winter-spring pruning is carried out after the roses shed their leaves and before they sprout, removing diseased and pest-infested branches, overly dense branches and aged branches, with appropriate short pruning to promote branching. For rose clumps with weak growth vigour and many old branches, appropriate heavy pruning should be carried out to promote the sprouting of new branches and restore vigour. Late-summer post-flowering pruning is mainly used for clumps with vigorous growth and dense branches, removing dense branches, crossing branches and overlapping branches, with appropriate light pruning.
Pest and Disease Control
The main pests and diseases of roses include rust, black spot, powdery mildew and scarab beetles. Rose gardens should be planted at a reasonable density, improve ventilation and light conditions, and reduce field humidity. Apply more phosphorus and potassium fertilizer to enhance plant disease resistance. After winter pruning, thoroughly clean the garden. In spring or during the growing period, promptly prune off branches harmed by rust, and manually catch scarab beetles, weevils, longhorn beetle larvae, etc. Before sprouting, spray 5 lime-sulfur mixture to eliminate overwintering pests and diseases. Spraying 200-fold dilution of Lorsban or phoxim, or making it into poisoned soil and broadcasting it on the soil of the tree basin, can kill large numbers of adult scarab beetles emerging from the soil. From May to June, spray 1000-fold dilution of 20% dicofol, 2000-4000-fold dilution of 73% propargite emulsifiable concentrate or 400-fold dilution of 50% sulfur suspension to control red spiders; from June to August, spray 2-3 times 600-fold dilution of 50% thiram wettable powder, 800-fold dilution of 50% thiophanate-methyl or 1:2:200 Bordeaux mixture to control damage.
Harvesting
MedicinalRose flowers（Kangmei Mall rose flowers), harvest when the flower buds are fully swollen but the flowers have not yet opened; when refining rose essential oil and using them for food, winemaking or scenting tea, they should be harvested when the flowers first open and the stamens have just emerged. Harvesting between 5 and 8 in the morning is most suitable. The freshly picked flowers should be dried in the sun, dried in the shade or oven-dried in a timely manner, and must be protected from moisture and light to avoid mould and deterioration.