You will have seen banks of orange and yellow flowers at the side of the road and been struck by their beauty. Close up, the trumpet shaped flowers of nasturtiums are even more stunning. Even the dark green, veined leaves are attractive.
Nasturtiums are annuals, but they set seed easily and will probably come up again in the same place next year, even without any help from you.
Harvesting nasturtium seeds is easy because they are large. Larger seeds will germinate better than small ones. Harvest green and brown seed alike, they will all grow. Just lift up the foliage and see where the seeds have fallen on the ground. You could even put black polythene around the flowers to catch any seeds as they fall. If your garden birds take some, so what, there are enough seeds for you and the birds. You can take ripe seeds from the plants, but it is rare for seeds to ripen fully before they fall.
You can plant your nasturtium seeds in March or April for a display of oranges, yellows and reds that will last from late July until the frosts.
Orange is not a common colour in most gardens, so nasturtiums provide extra interest in any sunny spot. They even flower better in poor soil than in rich soil, what more can you ask of any annual. They flower and flower without any dead-heading. I do not understand why nasturtium seeds are not planted in every garden.
Nasturtium seeds are large and easily handled. You can plant them straight into the soil in any sunny spot, or you can sow them in compost and then transplant the seedlings in a few weeks. Sow them a quarter of an inch deep and cover with soil or compost.
You can even eat the flowers. Use them in salads to provide a peppery taste and colour.