Look to ensure a distance
11.7 inches (30.0 cm) between Curly Rosy Posy seeds when sowing to make sure your seedlings have enough space.
By our calculations, you should look at sowing Curly Rosy Posy about 42 days before your last frost date.
As Curly Rosy Posy is hardy, ensure temperatures are mild enough to plant out - wait until after your last frost date to be on the safe side.