Look to ensure a distance
5.85 inches (15.0 cm) between seeds when sowing - bury at a depth of at least
0.98 inches (2.5 cm) deep.
By our calculations, you should look at sowing Zipper Cream about 0 days after your last frost date.
Ensure that temperatures are mild and all chance of frost has passed before planting out, as Zipper Cream is a tender plant.