The plants form rosettes of fleshy, lance shaped leaves in their first growing season which are unremarkable in appearance. But, in the spring this rosette begins to shoot skyward with leaves shrinking in size as they near the flowering scape.
Older plants may produce several blooming scapes, but young plants are usually unbranched.
The beautiful large spikes begin opening their drooping bell shaped blooms at the base of the scape, while the blooms above it are progressively smaller as they await their day of opening. The inside of the tubular flower is lighter coloured and marked with dark irregular blotches.
Digitalis are handsome and easy if watered well in dry weather, and look spectacular at the back of a border. The blooms are extremely attractive to bees
If you cut the stalk down before it goes to seed, it will generally rebloom and, if you wish, you can reseed from the second showing. The seedlings that spring up are easily transplanted to the location you want them to bloom.
Sowing: Sow indoors in March to May or sow directly outdoors in May to June or September to October
Sow seeds on the surface of a peaty soil. Do not cover or bury seeds as the seed needs light to germinate, just press seeds lightly into the earth. Keep seed in constant moisture (not wet) they will usually germinate in 2 to 4 weeks at around 20°C (68°F).
Sowing Indoors:
Sow in March to May, 10 to 12 weeks before last frost. Sow seed thinly in trays of compost and place in a cold frame or greenhouse. Once germination occurs keep in cooler conditions. Prick out each seedling as it becomes large enough to handle, transplant into 7.5cm (3in) pots or trays to grow on. Gradually acclimatise to outdoor conditions for 10 to 15 days before planting out once all risk of frost has gone. Transplant to the flowering position planting 30cm (12in) apart.
Sowing Direct:
Sow in May to June or September to October directly in a well prepared seedbed. Sow seed very thinly in drills 30cm (12in) apart. Firm down gently. Keep the plants moist and free of weeds. Thin out the seedlings to 15cm (6in) apart when large enough to handle.
Cultivation:
Digitalis purpurea foxgloves are biennial which means that plants establish and grow leaves in the first year, it will send up large spikes, then flower and produce seeds in the second.
As a rule, they are hardy plants and can cope with any soil unless it is very wet or very dry. They are fairly disease resistant, although the leaves may suffer slightly from powdery mildew if the summer is hot and humid.
If you cut the stalk down before it goes to seed, it will generally rebloom through August and, if you wish, you can reseed from the second showing.
Self-sown seedlings producing different shifting, untutored patterns of flowers each year, they can be easily transplanted to the location you want them to bloom. They are best transplanted when the leaves are about 10cm long. Make sure the newly moved plants are watered very well to help them establish.