Keep in mind when planting that Winky Double White-White is thought of as very hardy, so this plant will tend to go dormant over the long winter months.
Try to ensure a gap of at least
11.89 inches (30.48 cm) when sowing to prevent overcrowding your seedlings.
By our calculations, you should look at sowing Winky Double White-White about 56 days before your last frost date.
As Winky Double White-White is very hardy, ensure temperatures are mild enough to plant out - wait until after your last frost date to be on the safe side.