Variety selection

There are many varieties of Platycodon grandiflorum, which can be roughly divided into early-growing, middle-growing and late-growing varieties. The suitable cultivation period of early-growing varieties is March, August and September, the suitable cultivation period of middle-growing varieties is March, July and August, and the suitable cultivation period of late-growing varieties is March to July, while the seedling period is usually two months

Therefore, sowing should be selected according to different varieties, and about two months in advance before it is suitable for transplanting

Preparation before sowing

The substrate is slightly alkaline, and the pH value is maintained at 6-6.5. Peat can be added with some vermiculite and perlite. After adding some Carbendazim and stirring, the substrate is disinfected to prevent the breeding of bacteria

Before sowing, water the substrate to keep it moist

Sowing method

After preparing the substrate, sprinkle the seeds evenly on the surface of the soil without covering the soil, and then spray some with carbendazim diluent to improve the adhesion and antibacterial property of the seeds

Keep the light and maintain the temperature at about 20 ℃ - 25 ℃, and pay attention to maintaining the moisture of the substrate at the seedling stage

Generally, the seedlings will appear after two weeks. After emergence, transfer the Platycodon grandiflorum to a ventilated place and reduce the temperature to about 15 ℃. Note that the temperature should not exceed 25 ℃ in the daytime and 5 ℃ at night. At this time, 100-150ppm nitrogen fertilizer can be applied

Transplanting after sowing

The seedlings can be transplanted when they grow two pairs of true leaves. Do not damage the roots when transplanting. Low temperature, dryness, insufficient light and excessive nitrogen fertilizer are easy to cause bud abortion

Don't plant too deep to avoid stem rot. keep the temperature at 13 ℃ - 23 ℃. Pour water after transplanting, but reduce the number of watering in the later stage. Generally, the proportion of watering in sunny days is: morning: Day: night = 2:2:1. Don't suddenly reduce watering in high temperature