Quick-growing summer annuals can add nearly instant color to your garden beds and planters. Nasturtiums (Tropaeolum spp.) produce yellow, orange and red flowers, usually on the same plant. These annual flowers grow readily in USDA zones 2 to 11, and planting nasturtiums from seed is inexpensive enough that you can grow plenty of them with minimal effort and cost. Encourage good sprouting by preparing and planting the seeds correctly.
Sprouting Nasturtiums Indoors
A standard sterile potting mix works well for starting nasturtium seeds indoors. Use individual 2- to 3-inch-diameter seedling pots or a larger seedling tray. Pots and trays must have drainage holes so the excess water can drain out. Water the soil before you plant so it’s moist. Sow a single seed per pot, or plant the seeds 2 inches apart in rows set 2 inches apart in a tray.
Nasturtium seeds are large and require deep planting, so plant the seeds 1/2- to 1-inch deep in the pots. Keeping the soil temperature near 70 degrees Fahrenheit and maintaining even moisture encourages quick germination. The nasturtium seedlings won’t require light until after they sprout.
Sowing Nasturtiums Outdoors
It’s possible to sow nasturtium seeds directly in the garden bed if you prepare the soil first. Nasturtiums have few soil needs. Choose a well-drained bed that receives at least six hours of sunlight daily and work up to 2 inches of compost into it first to improve drainage and quality. Once prepared, plant the seeds 1/2- to 1-inch deep and space them 3 inches apart. The soil will require watering so the top 6 inches remains moist. Once the nasturtiums sprout, thin the plants so they have 8 to 10 inches of space on all sides.
Growing On
Nasturtiums are easy to care for, but it’s important that you water them during periods of drought. The soil should not dry out too much without frequent watering as this plant will become soggy and unproductive in containers or window boxes. They also need regular feedings using fertilizer so they have plenty blooms all summer long!
Nasturtiums are an exciting addition to the salad bowl, with their peppery taste reminiscent of watercress. All colors and varieties can be enjoyed in salads or on top garnishes! The leaves even make for tasty additions too so plant some today – you won’t regret it!
