Annual and biennial rudbeckias can be grown from seed. Sow seed in early spring and keep seedlings under cover until large enough to handle and pot on, then harden off after danger of frost has passed. Plant out in May. Perennial rudbeckias can be planted at any time of year.
Most should be sown some time between February and April. Seeds will take around 14-21 days to germinate. As the seedlings begin to grow they should be individually potted on or thinned to around 30cm apart. This is to allow them to become full and healthy plants by the time you come to plant them out in the autumn.
Rudbeckia can be started indoors, from seed, about 6-8 weeks before last expected frost. Perennial varieties will germinate best if stratified after planting. You can do this by keeping them in the refrigerator or a similarly cold place for 4 weeks after planting.. . . . .364011234961!]
