Starting
Sow seeds 5mm – 1cm (¼”-½”) deep. If starting indoors, provide darkness during germination, followed by bright light. Space smaller varieties 15-30cm (6-12″) apart, and the big ones like Tall Single 60-90cm (24-36″) apart.

Growing
Nasturtiums thrive in poor to average, slightly acidic, well-drained soil. Grown in full sun, you might consider using some rocks around the plants to prevent their roots from getting too hot. In partial shade, plants tend to have larger leaves and a more sprawling habit. Keep watered during dry weather, and do not fertilize. If aphids infest your nasturtiums, cut off the infested growing tip and destroy it. Otherwise, a quick jet of water from the hose will dislodge and kill aphids.