For cold moist treatment in the garden: The best is to use deep pots with gravel in the bottom for drainage. Seeds are deposited on the surface of the potting soil and covered with about 2 cm of a mix of coarse and fine sand. Pots are then protected with metal mesh to prevent birds and mice from having a banquet of the seeds. Pots will be placed outside for the winter. In Spring, when the seedlings emerge, the pots are moved to a semi-shaded location.

If sowing indoor: The potted seedlings may be placed in bright, indirect light, and the soil kept moist. The little seedlings have dark green or sometimes reddish cotyledons. The pale yellow or white seedlings should be removed, they will die from chlorosis. The first two or three true leaves are smooth. It is only from the third leaf that they become runcinate (having a saw-toothed margin with the teeth pointing backwards). All seedlings which have misshapen leaves should be pulled as they won't produce good flowers. After the fourth or seventh leaf, the flower bud will appear. The following process, selection, starts here.