What are the propagation methods for Caragana arborescens?

  Caragana arborescens is generally propagated by sowing. Its seeds mostly mature in early August; when the pods turn dark yellow they should be picked promptly, for if picked too late the seeds will burst from the pods and scatter, making them hard to collect. Spread the collected seed pods in the sun to dry so the seeds shed naturally from the pods, then after cleaning store the seeds in a clean cloth bag in a shaded, ventilated place. In mid-March of the following year, soak them in 45°C warm water for 48 hours before sowing.

  Choose fertile, flat, well-drained sandy loam as the nursery site, and apply decomposed and fermented cow or horse manure as base fertilizer at a rate of 3500 kg per mu; the base fertilizer should be mixed evenly with the nursery soil, then after sun-drying, rake it fine and level it, and disinfect the seedbed with quintozene. Broadcasting can be used for sowing, with a seeding rate of 20 g to 25 g per sq m; after sowing, tread lightly with the foot and give one sprinkler irrigation.

  During seed germination keep the soil moist; once the seedlings emerge evenly, irrigate once every 5 to 7 days, each time watering thoroughly, and it is best to irrigate in the early morning or evening. When the seedlings reach about 20 cm, thin them. Carry out thinning on overcast or rainy days, and operate carefully to avoid damaging other seedlings.

  To promote faster seedling growth, apply a topdressing of urea once in mid-June and a topdressing of phosphorus and potassium fertilizer once in early August, watering promptly after each topdressing. Transplanting can be done after two years.