Keep in mind when planting that Amelia 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).
Growing Amelia from seed
By our calculations, you should look at sowing Amelia about 90 days before your last frost date.
Transplanting Amelia
As Amelia is hardy, ensure temperatures are mild enough to plant out - wait until after your last frost date to be on the safe side.