The first important thing for sowing and propagation is to collect seeds on the old catalpa tree which is more than 20 years old, and then store them after drying. Then soak the seeds in warm water of about 30 ℃ for 4 hours before sowing, then dry them, mix the seeds with wet sand evenly and wait for sprouting. In the meantime, it is necessary to sprinkle water and turn it regularly, so that the humidity inside and outside is even, and seeds can be sown after opening.
The grafting of Catalpa can be carried out in winter or spring, bud grafting can be carried out in spring or late autumn, wet sand storage can be carried out after indoor grafting in winter, and planting can be carried out at the beginning of spring, grafting before and after Qingming is better, and the survival rate of grafting while sealing soil is higher. In addition, splitting method can be used, that is, preparing the scion and stock needed, tying the formation layer with hemp rope and plastic rope, and sealing with wet soil. Sprout in about 10 days.
The propagation of burying roots of catalpa tree can be selected in the late March, and the roots of 1-2cm are selected on the well-developed catalpa tree, the length is between 12-20cm, the incision should be smooth, and the roots should be buried obliquely in the soil. When burying roots, the surrounding soil should be pressed to make it compact, and then water can be poured.
Just as the name implies, flat burying is to put the root into the soil so that the soil can be compacted. After burying, it can sprout about 20 days later, and then carry out tillering. Only one branch with good growth can be kept on each one.
