- You can start the seeds indoors 4 to 6 weeks before the last spring frost.
- Plant seeds in early spring in moist, well-drained soil in full sun. They can grow in partial shade, but they will not bloom as well.
- Nasturtiums prefer poorer soils and they do not need fertilizers (unless your soil is extremely poor). Fertile soil will produce fewer blooms.
- Plant the seeds about half an inch deep and 10 to 12 inches apart. Plants should appear in 7 to 10 days.
- Water regularly throughout the growing season, but be careful not to over-water your plants.
- Cutting off the faded/dead flowers will prolong blooming.
- If you're growing nasturtiums in containers, they may need to be trimmed back occasionally over the growing season.
Save the nasturtium chick-pea-size seeds and replant in the spring! Let them dry out on the vine; they'll fall off. Collect them, brush off the soil, dry them, and store them in a paper envelope in a cool and dark place.