Nasturtium seeds should be sown outdoors, if possible. If not, plant the seeds in peat pots to avoid the shock of transplanting. Nick the seeds and place them in lukewarm water overnight for faster germination. Nasturtiums need an area with plenty of room for growth, with a trellis placed nearby for climbing varieties.
Nasturtiums require little fertilizer and can thrive in areas with poor soil. Regular weekly watering keeps the foliage and flowers healthy. Their soil should be well-drained. For large blooms, they need full to partial sun.
Nasturtium varieties can be bush plants, trailing vines or climbers. They have brightly colored flowers that form an open funnel shape. The flowers appear in early summer through fall in cooler climates and fall through spring in milder ones. Their leaves are rounded, with a few varieties being variegated. The leaves and flowers are both edible. They have a peppery taste and are sometimes added to salads. The seed pods are sometimes used as a substitute for capers.
Aphids love nasturtiums. Many gardeners plant nasturtiums in vegetable gardens to draw the pests away from other plants. To get rid of aphids, blast the plant with water. Flea beetles, slugs and caterpillars are other common nasturtium pests.