Keep in mind when planting that Marmalade 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
4.68 inches (12.0 cm) when sowing to prevent overcrowding your seedlings.
By our calculations, you should look at sowing Marmalade about 63 days before your last frost date.
Ensure that temperatures are mild and all chance of frost has passed before planting out, as Marmalade is a very hardy plant.