Tropaeolum (group)
Common Name: nasturtium
Type: Annual
Family: Tropaeolaceae
Zone: 2 to 11
Height: 1.00 to 10.00 feet
Spread: 1.00 to 3.00 feet
Bloom Time: May to September
Bloom Description: Red, orange, yellow or cream
Sun: Full sun
Water: Medium
Maintenance: Low
Suggested Use: Annual
Flower: Showy, Fragrant
Attracts: Butterflies
Tolerate: Deer

Culture

Grow in poor to average, slightly acidic, well-drained soils in full sun. Plants have some tolerance for dry soils. Best performance occurs in cool summer areas. Some part afternoon shade is appreciated in hot summer areas where plants will be stressed by prolonged stretches of high temperatures. Avoid fertilization which tends to increase foliage output but decrease flower production. By reputation, nasturtiums are easy-to-grow annuals that are tolerant of a certain amount of neglect. Sow seed directly in the garden near last spring frost date, or in pots about 4-6 weeks prior to last spring frost date. Propagate by cuttings or by seed. Plants will self seed in the garden.

Noteworthy Characteristics

Nasturtiums are warm weather annuals that have been popular in herb gardens, cottage gardens and flower gardens for many years. Cultivars and hybrids sold under the name of Tropaeolum majus are generally referred to as common nasturtiums or garden nasturtiums. These plants feature showy, long-stalked, spurred, funnel-shaped, 5-petaled flowers (to 2.5” wide) in shades of red, orange, yellow and cream. Flowers have a spicy fragrance. Flowers bloom from spring to fall. Rounded, long-petioled, parasol-like leaves of these plants are peltate (petioles attached near the center of each leaf). These plants appear as climbing types (to 6-10’) and as dwarf-bushy sprawling types (to 1’ tall and 2’ wide).

Genus name comes from the Greek word tropaion meaning a trophy and the Latin word tropaeum named by Linnaeus for its resemblance to a classical trophy.

Current dwarf-bushy varieties include Alaska Series (to 12” tall with white spotted leaves), Gleam Series (semi-trailing to 18” tall with semi-double flowers), Jewel Series (dwarf-bushy to 12” tall with semi-double and double flowers), Tom Thumb Series (dwarf-bushy to 10” tall with single flowers) and Whirlybird Series (dwarf-bushy to 10” tall with spurless single to semi-double flowers). ‘Jewel of Africa’ climbs to 8’ tall with single flowers and white spotted leaves.

Problems

No serious insect or disease problems. Watch for aphids, mealybugs and whiteflies.

Garden Uses

Dwarf-bushy, sprawling types are effective in beds, borders, mixed plantings, rock gardens, herb gardens, edgings over walls or as annual ground covers on slopes or other sunny areas. They are also effective in containers, including hanging baskets. Climbing types should be trained on a support (trellis or fence). Except for roots, all plant parts (leaves, buds, flowers, pods and seeds) are edible (peppery flavor) and may be used in salads.