Dahlia likes sunny, well-ventilated, cool environment, neither cold nor hot, neither dry nor wet nor waterlogging. Suitable for planting on fertile, loose and well-drained sandy soil.
Usually by rooting and cutting propagation. Root splitting propagation is to split the cellar roots with a sharp knife in early spring, each root needs 1 ~ 2 neck buds, the incision is coated with plant ash or sulfur powder, and then planted. Cutting propagation is to put the tuberous roots stored in winter into the greenhouse in turn, cover them with wet sand, expose the root neck, accelerate germination at 15 ~ 22℃, cut when the plant height is 6 ~ 7 cm, leave two leaves, take root after 20 days, and then put them in the pot. In recent years, the dwarf dahlia introduced from abroad is propagated by seeds, harvested in autumn and raised in spring. Besides, seeds are only used for breeding.
Dahlia can be planted on the ground and potted. In-situ planting refers to planting tubers, cuttings or seeds in Miao Di after late frost, paying attention to fertilizer and water management, increasing fertilizer and controlling water, and properly controlling plant height. Dig out the rhizome after the frost in late autumn, dry it in the shade and store it in sand. Do not water when storing sand, and control the temperature at 3 ~ 5℃. Potting is when the seedling height is about 10 cm. Small pots were used at first, and then the diameter of the pots was gradually increased with the growth of plants. Dahlia likes fertilizer, except base fertilizer, which should be topdressing every 10 day 1 time. For many varieties, especially dwarf varieties, the core should be picked at the plant height 10 ~ 20 cm to promote the growth of lateral branches, and the core should be picked for 2 ~ 3 times, leaving only 2 nodes each time. The ornamental value of Dahlia has been greatly improved after the core removal and plastic surgery.
Dahlia is prone to root rot, and the soil is too wet and the drainage is not smooth. Therefore, attention should be paid to drainage and waterlogging prevention, and continuous cropping is not allowed. Pests are mainly aphids and red spiders, which can be controlled by omethoate.
Dahlias are brightly colored, big and colorful. It is suitable for planting in flower beds, flower borders or courtyards, potted plants or as cut flowers.