(1) technical characteristics of seedling raising. The temperature requirement is strict. The most suitable ground temperature for Salvia splendens seeds is 23 ~ 26℃, and it is difficult to germinate below 65438 05℃. When the ground temperature is low, the days of germination and excavation increase obviously. This can be seen clearly in the spring electric hotbed seedling raising. The seedling tray placed on the electric hotbed is close to the bed surface of the electric hotbed, and the temperature is relatively low, and the seedling emergence is about 1 day. The optimum temperature for seedling growth and development is 20 ~ 25℃. When the temperature is higher than 30℃, the growth is inhibited, and when it is lower than 15℃, the growth is slow. Flower bud differentiation needs short sunshine, and the conditions for seedling raising in spring are just right. Strict requirements for soil moisture. In the middle and early stage of seedling raising, excessive water control is easy to form small seedlings and old seedlings. In the middle and late stage of seedling raising, there is too much soil moisture, insufficient nutrient area and insufficient illumination, and it is easy to grow white when the temperature is high at night. Throughout the seedling stage, people are afraid of drought and waterlogging. It is easy to collapse at seedling stage. Soil bacteria, low temperature and high humidity are the internal and external causes of the disease. At present, it usually takes 90 ~ 100 days to cultivate large bud seedlings from winter to early spring, and it takes 10 ~ 20 cm long/inflorescence 1/kloc-0 ~120 days. Of course, there are also imported varieties that bloom early, such as small tango series and flame, but they are rarely cultivated in China.
(2) Seed preparation. The 1000-grain weight of a bunch of red seeds is 3 ~ 4 grams, and the seeds are black. The service life of seeds is 3 ~ 4 years. At present, commercial planting mostly adopts hybrid generation, which is expensive, and the price of each seed is more than 4 cents RMB. Have a plenty of varieties, you can collect seeds by yourself, and you should collect more seeds every year in special years when you can't receive seeds. A bunch of red nuts are easy to fall off when they are ripe, so they should be harvested in time. The calyx in the middle of the whole inflorescence is light, so cut off the whole inflorescence when the nuts are just ripe. Sun drying and threshing to remove immature seeds.
(3) Seeding and seedling raising. Seedlings are strict with nutrient soil, so they need to sow loose and fertile nutrient soil. Put the sieved nutrient soil into the seedbed or seedling tray, pour it thoroughly, then sprinkle with medicinal soil (except those that have been disinfected in advance), then sow, the sowing amount is about 25g per square meter of seedbed, and then sprinkle with medicinal soil. Cover the seeds with fine soil (medicinal soil) about 1 cm. Or soak the seeds to be sown in warm water at 30 ~ 35℃, soak the seeds for 4 ~ 6 hours in the current year and 8 ~ 12 hours in the next year, then take them out and spread them on gauze, and sow them immediately after the surface of the seeds is dry. The ground temperature is controlled at 22 ~ 25℃, and the seeds emerge after 5 days of dry sowing. When there are 1 pairs of slightly larger true leaves, first cultivate seedlings with 72 holes or 128 holes. When the seedlings grow to be crowded with each other, move them into a container with a diameter of about 8 cm to cultivate large seedlings with buds, or furrow them to become seedlings. Only transplanting 1 seedling is more beneficial to growth, but the production cost of heating seedling is higher. If larger flowering plants are to be cultivated, they should be transplanted into containers with a diameter of 12 ~ 15 cm.
During the emergence and slow seedling stage, the temperature is controlled at 25 ~ 30℃ during the day, 18 ~ 20℃ at night, 20 ~ 25℃ at other times and 10 ~ 15℃ at night. Cooling to about 5℃ at night 5 ~ 7 days before planting. See the light as fully as possible, always keep the cover clean when raising seedlings in protected areas, and clean up the dust on plastic film or glass in time. It takes a long time to plant a pile of red seedlings, which grow in fertile and loose soil. If the symptoms of fertilizer deficiency appear in the middle and late stage of seedling raising, you can water it several times with 3000 times of NPK compound fertilizer, generally with 1 times of fertilizer water, and then water it twice with clear water. Salvia splendens is very sensitive to the excessive concentration of salt ions in the soil, so don't apply too much fertilizer when using soil to raise seedlings. Moderately control soil moisture.
If you let the main inflorescence blossom first, don't be picky. If there are 2 ~ 4 lateral branches flowering, it is not too late to pick the heart when there are 2 ~ 3 pairs of leaves, and leave 2 ~ 4 lateral branches in the future.
(4) Cutting propagation. The cuttage propagation of Salvia splendens is easy, and it blooms early. When raising seedlings with expensive seeds, cutting propagation can be combined to reduce the cost of raising seedlings. In autumn, plants will be moved to the greenhouse for the winter. In early spring, branches of about 10cm will be cut into cuttings, or expensive fine seeds will be sown in advance, and the seedlings cultivated by them will be used as mother plants. When there are 4-5 pairs of true leaves, pick up the cuttings and use them for lateral insertion later. Cutting on the sand bed, the ground temperature is controlled at 20 ~ 22℃, and when the light is strong, it is shaded properly. After cutting 10 days, it begins to take root, and then it is moved into a container to become seedlings.