Abstract
We investigated the seed germination characteristics of Hydrangea petiolaris to use this species for greening. In laboratory experiments, optimum temperature for germination ranged from 25 °C to 30 °C and germination percentages were promoted by alternating temperatures under light condition. Highest germination percentage was 100 % at 30/20 °C. Seeds germinated less than 2 % below 20 °C. However, seeds given cold stratification germinated to 69 % even at 10 °C. Seeds stored in dry condition at 5 °C maintained their germinability for one year. Seeds need light to germinate irrespective of the temperature, cold stratification, or periods of dry storage. In field experiments, seeds sown between November and July of following year germinated to about 60 % until mid-August. When we grow the seedlings, seeds stored at 5 °C should be sown from late April to early May without soil covering.
