Large seeds of nasturtium plants should be sown directly into their permanent location, as nasturtium flowers do not transplant well. If you must start seeds of nasturtium flowers and then transplant them, use peat pots that can be planted into the ground without disturbing the roots of the growing nasturtium seedling. The seed coat may be manipulated for faster germination when growing nasturtium; nick the seed with a nail file or sandpaper, or soak overnight in lukewarm water. Plant immediately into a container or area of the garden which allows plenty of room for growth.
Plant 2-3 cm deep. Keep soil moist during the germination period.