Keep in mind when planting that Blue Asagao Willow is thought of as tender, so remember to ensure that temperatures are mild before moving outdoors.
By our calculations, you should look at sowing Blue Asagao Willow about 25 days before your last frost date.
As Blue Asagao Willow is tender, ensure temperatures are mild enough to plant out - wait until after your last frost date to be on the safe side.