Members of the Buttercup family are called Ranunculaceae. To grow the plants successfully beware the seeds tend to have a short period of viability and need planting straight away.
Seed merchant advice (but they want to sell seeds all year around.) ‘Sow April to May or September to October. Alternatively, sow in late summer in 7.5cm (3in) pots in a cool greenhouse and then overwinter plants in cool, well lit conditions. Sow outdoors where they are to flower. Prepare the ground well and rake to a fine tilth before sowing. Sow 3mm (1/8in) deep, in rows 30cm (12in) apart. When large enough to handle, thin out seedlings to 23cm (9in) apart.’
Photo Credits trollius by withrow CC BY-NC 2.0 nigella by ripplestone garden CC BY-ND 2.0
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