For flashy flowers and bold foliage, it's tough to beat New Guinea impatiens. These summer annuals come in a palette of brilliant colors, from hot pink and bright orange to red. Their foliage, in mostly solid colors ranging from green to bronze to burgundy, makes them easy to use in the garden and in containers. And with blooms that can reach 3 inches in diameter, they're sure to grab attention.
Plant a few New Guineas this month; they'll bloom until weather turns cold.
Smaller sizes. Plants in the new generation of New Guinea impatiens are more compact. The shortest of these ― in the Celebrette, Compact Sonic, and Paradise series ― range from 8 to 18 inches tall and are especially suited to smaller containers. Plants in the more vigorous Celebration, Pure Beauty, and Super Sonic series grow 18 to 24 inches tall and perform well in large containers and the landscape.
New hybrids, new uses. Two new series ― hybrids between New Guineas and other impatiens species ― can take more heat than standard New Guinea impatiens.
Sun lovers. SunPatiens, developed by Japanese breeders, thrive in full sun and heat and grow 15 to 20 inches tall. There are three brightly colored varieties ― 'Tropical Mango', 'Tropical Orange', and 'Tropical Punch' ― as well as the white 'Tropical Ice'. In tests at Sunset's headquarters, the plants bloomed prolifically over a long period. Grow them in pots or in the ground.
Trailer. Fanfare (shown at top left) is a mounding, trailing heat-resistant impatiens that's perfect for containers and hanging baskets. The flowers are slightly smaller than standard New Guinea impatiens, but they blanket the plant all season long. Flowers come in four bright colors as well as blush.
Among the New Guinea impatiens and related hybrids are six that we grew and liked in Sunset's test garden. Their flowers, which now come in a broader color range than ever before, vary from brilliant solid hues to bicolors and measure about 3 inches across.
New Guinea impatiens look particularly striking mingled with coleus, heuchera, and other colorful foliage plants that thrive in part sun.
• Celebrette 'Purple Improved' and Magilla 'Purple' perilla
• Infinity 'Scarlet' with 'Black Heart' ipomoea, red-leafed Abyssinian banana, and 'Troy's Gold' plectranthus
• Paradise 'Orchid' with 'Illustris' colocasia, lime green coleus, and 'Purple Ruffles' heuchera
• Sonic 'Cattleya' with maroon and pink 'Kingswood Torch' coleus and 'Margarita' ipomoea
• SunPatiens 'Tropical Ice' with Chinese taro and white bacopa
Temperature. Plant after the soil warms and nighttime temperatures are above 50°. In general, plants stop blooming when temperatures soar to 85° or more. In hot, inland areas, choose plants from one of the heat-resistant series ― Celebrette, Fanfare, or SunPatiens.
Sun. New Guinea impatiens need some sun to bloom well. Choose an area that gets morning sun and afternoon shade (protect from midday sun). In cool, coastal areas, plant in full sun.
Soil. Plant in soil that's well drained but not too rich. Mix in an organic or a controlled-release fertilizer low in nitrogen.
Water. Keep the soil moist but not soggy.