It is propagated by seed sowing. The suitable temperature for germination is 28-32°C, but the seeds are not resistant to storage. They should be harvested and sown busy. During the growth period, topdressing once every 1-2 months can make them grow well.
Store in sand for 60 days before sowing or soak the seeds in warm water to promote germination. When planting on high borders, water should not be accumulated on the borders. After sowing, they can be covered with plastic film to improve soil temperature and maintain moisture. It takes about 15 to 20 days to germinate and unearth. The film should be removed immediately after the seedlings are in place, and a layer of sawdust should be sprinkled between the rows to preserve moisture and prevent the seedlings from being splashed with mud when watering. The border soil should not be too wet to avoid damping off. The height of the seedlings in that year was 5-7 cm, and the cold resistance was poor. The northern seedlings should be buried in soil to prevent cold. If conditions permit, it is best to build a shade shade for a month after emergence to prevent high temperature and sunburn. In the spring of the second year, the bare root seedlings can be transplanted, and then transplanted with soil again after 2 years, and the seedlings can be cultivated to a height of 30 cm. Large seedlings are often used in gardens, so they have to be transplanted again.
For seeds with hard seed coats and need to break dormancy, the treatment method of mixed sand and low temperature stratification is generally used. In the seed treatment, it was found that most of the seeds need dark treatment to avoid light when they are stratified at low temperature. And the longer the time of low temperature stratification of seeds, the higher the germination rate and the more uniform the emergence. In spring, prepare the ground, turn the ground and harrow the ground. Make a 1m wide seedbed, and use Fe2SO4 or phoxim for soil disinfection. The sowing time is from the end of April to the beginning of May in spring or in autumn, and the sowing depth varies from 0.5 to 20 cm. The sowing method generally adopts drill seeding, and the row spacing is 8~10cm. The plant spacing is controlled at about 2cm.
