2. Soil texture: permeablility or breathability good loam and sand soil, avoid clay, harden, ventilation adverse soil.
3. PH of soil, 6-7.5 is the best, 5-8.9 is acceptable.
4. Good irrigation and drainage systerm will be better.
5. Elevation up to 2000m is acceptable
1. Fecund and wet. No ponding and water saturation
2. Annual rainfull 400mm-1200mm.
3. In seedling period, keep the soil with good moisture(around 30%), after grow up than 50cm drought resistant ability improve, then better and better.
1. Plant paulownia tree in sunny place and keep away from heavy wind.
2. Try to prohibit paulownia tree under other bigger trees
3. Density. For seedling using 0.8x1m or 1x1m distance, for forestation 4x4m or bigger distance.
Plant with crop distance more than 3x15m.
Annual temperature 12-20celsius degree grow better; -20-45celsius degree is ok, vulnerable to frost damage if absolute temperature less than -25celsius degree.
1. Hybrid by paulownia fortunei x tomentosa, parents are south and north species of Chinese.
2. The hybrid species inherited good gene of the both, has good environmental adaptability.
3. Fast growth, with medium crown, straight through trunk, small difference between top and end.
4. The first 1-3years fast growth of height, the first year 3-5m, the following more than 2-3m per year. From 3-4years height slowly and coarse grow faster, 4-9years is the fast period of thickness. 10years grow slowly and steadily. So the paulownia tree 7-10years mature, up to 0.8-1cbm per tree.