Transplant the self sown seedlings where you want them in the garden.
Try to plant in a location that enjoys full sun and remember to water very sparingly. Keep in mind when planting that Angel's Blush is thought of as hardy, so it can be safe to leave outdoors for the majority of winter (although if in doubt, using a row cover is often a good idea).By our calculations, you should look at sowing Angel's Blush about 49 days before your last frost date.
Lychnis coronaria