This time no seed pods, only withered flowers, but it was so interesting I thought I should post it here.
I've already wrote about this nice bluebell in a post in June.
Campanula raddeana
It is characteristic to bluebells (Campanula) that the pollen is ripe already when the flower is not yet open. This partly prevents self pollination because the stigma becomes receptive only after the opening of the flower. As the sticky style is elongating and pushing itself through the other parts of the flower, it collects pollen grains:
In case of Campanula raddeana the stamens interestingly curl back after the anthers had released the pollen.
Later the stigma splits to three parts and from now on it is ready to welcome the pollen. If there is still some fertile pollen grain around.
On the following picture you can se the split stigma, but don't be deceived! It splits when the flower is still fresh, this picture was taken a little too late.
Self pollination in general is not common to bluebells, but sometimes happens. I don't know what about this species but I think it is not self fertile. There were many flowers in June but no seeds at all. According to botanists there are many insects visiting bluebells but their pollination capacity is not the same.
Now it is flowering again, though not so abundantly as in June.
Here you can se better the curled stamens and the stigma and style with pollen. To show this, I had to pull off the wilted, papery petals – it was not easy.
In case of Campanula raddeana the stamens interestingly curl back after the anthers had released the pollen.
Later the stigma splits to three parts and from now on it is ready to welcome the pollen. If there is still some fertile pollen grain around.
On the following picture you can se the split stigma, but don't be deceived! It splits when the flower is still fresh, this picture was taken a little too late.
Self pollination in general is not common to bluebells, but sometimes happens. I don't know what about this species but I think it is not self fertile. There were many flowers in June but no seeds at all. According to botanists there are many insects visiting bluebells but their pollination capacity is not the same.
Now it is flowering again, though not so abundantly as in June.
Here you can se better the curled stamens and the stigma and style with pollen. To show this, I had to pull off the wilted, papery petals – it was not easy.
It would be nice to collect some seeds from this pretty Campanula, but I don't think I will have the opportunity...
Source – except of my observations confirmed on my pictures –: Graham Nicholls Dwarf Campanulas (Timber Press, 2006), and some abstracts of scientific papers found on the net.
Source – except of my observations confirmed on my pictures –: Graham Nicholls Dwarf Campanulas (Timber Press, 2006), and some abstracts of scientific papers found on the net.
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