|Foxglove and Sedum|
The flowers on foxglove (Digitalis purpurea) open first at the bottom and work their way up over a period of weeks. The reasons given for this are twofold. Firstly, it gives security against bad weather which will keep bees, their main pollinators, in bed until it cheers up and secondly, its normal habitat is in areas where tall grasses and other plant are liable to grow up around it and hide the flowers from bees, so later flowering to the tip of its spire ensures they will still be seen. Nectar is secreted at the base of the flower, attracting bees which follow the 'runway' marked out with spots. They have to force their way down the flower to the nectar and, in so doing, rub past the anthers, picking up pollen which gets transferred to the next plant they visit.
|Yellow foxglove (Digitalis grandiflora) which arrived uninvited|
As it is throughout life, you can have too much of a good thing and poisonous foxglove is a case in point: the right amount can save your life, whereas a bit too much can lead to the funeral insurance being cashed in.