Keep in mind when planting that Alba 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 Alba from seed
By our calculations, you should look at sowing Alba about 63 days before your last frost date.
Transplanting Alba
Ensure that temperatures are mild and all chance of frost has passed before planting out, as Alba is a hardy plant.