Wedding Bells is generally regarded as a tender plant, so remember to wait until your soil is warm and the night time temperature is well above freezing before moving outside.
Growing Wedding Bells from seed
By our calculations, you should look at sowing Wedding Bells about 25 days before your last frost date.
Transplanting Wedding Bells
Wedding Bells is tender, so ensure you wait until all danger of frost has passed in your area before considering planting outside.