(1) soil, water and fertilizer management: roses are not very selective to soil, but they grow best in sandy loam rich in humus, whether planted on the ground or potted. Roses are moist, but they are afraid of dampness and avoid waterlogging, so attention should be paid to good drainage when planting or potted on the ground. The water should be "thoroughly dried". From germination to flowering, you can properly water more, and the soil should be moist and not waterlogged. After flowering, don't water too much, and the soil should be dry and wet. Pay attention to drainage and flood prevention in rainy season. It likes fertilizer, but it also endures poverty. According to the principle of "thin fertilizer and diligent application", various nutrients are continuously supplied. In March, 1 ~ 2 times liquid fertilizer mainly containing nitrogen can be applied to promote the growth of branches and leaves, and from April to early May, 2 ~ 3 times fertilizer mainly containing phosphorus and potassium can be applied to promote more buds, stronger buds and brighter flowers, and then rejuvenation fertilizer can be applied after flowering. Appropriate amount of organic fertilizer should be applied in late autumn to nourish winter roots.
(2) Requirements for light, temperature and humidity: Roses are masculine flowers, and they like temperature and cold tolerance. It can be planted in the open air in North China and its south, and it needs to be loosened and ventilated. Potted roses should be properly shaded in summer to avoid sun exposure, and the leaves should be sprayed with water to increase air humidity, and they should be kept warm in winter to prevent the roots from freezing.
(3) Shaping and pruning: for planting in the open field, a shed should be set up or other trunks should be wrapped with trunks. Ventilation and light transmission are very important in summer. The robust branches that grow on the main stem or vine every year can be properly retained to renew the old branches and weak branches, and the redundant branches are cut off at the base. In late summer and early autumn, the branches and vines with irregular growth and uneven distribution can be adjusted, pulled and tied at any time to ensure ventilation and light transmission during the growing season. From late winter to early spring, the plants were carefully pruned, with the focus on retracting the annual branches and cutting off about 1/3.
It is best to leave 3 ~ 5 main branches on the stem of potted roses, the main branches should not be too long, and the side branches on the main branches should be shorter. In winter, only 1 ~ 2 flower buds are left on the annual branches on the lateral branches, and all the upper parts can be cut off.
(4) Pest control: roses are prone to powdery mildew. Once found, cut off the diseased branches and burn them to avoid infection, and spray 200 times Bordeaux solution or 800 times 70% thiophanate methyl solution.