Abstract:

Plants of the genus Clematis，which has been featured long florescence，various flower pattern and color. To investigate the flowering characteristics of Clematis in the middle and lower reaches of Yangtze river in China，9 primary florescence characteristics including squaring stage，bud stage，initial flowering stage，fullbloom stage，wither stage，last flowering stage，florescence，ornamental period and single flower florescence of 79 ornamental Clematis cultivars were observed and analysised in three consecutive years. Seventy-nine cultivars were categorized into 5 groups，including extremely early group，early group，medium group，late group，and extremely late group，according to the initial flowering stage data with 16 days as the differential. And according to the gradient of five days of ornamental period，79 cultivars were categorized into another five groups，including very short flowering phase，short flowering phase，medium flowering phase，long flowering phase，very long flowering phase. CDI analysis showed that late April to late May were the best ornamental period of Clematis. Correlation analysis showed that the bud stage，florescence and ornamental period were significantly correlated to the temperature，while single flower has no such correlation. This paper could lay a foundation for the study on the flowering traits of Clematis，provide a theoretical basis for the landscape garden application，planting varieties collocation，specialized garden construction，and breeding parental select.