How to Grow and Care for New Guinea Impatiens

New Guinea Impatiens
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Few flowers are as popular as impatiens, (Impatiens walleriana). They are one of the few flowers that bloom continuously and thrive in shade, with little care. If you've ever wished you could find a similar long bloomer for a sunny spot in the garden, take a look at their cousins, the New Guinea impatiens, Impatiens hawkeri.

New Guinea impatiens form small clumps and hold their many flowers above their foliage, where they make a colorful display. No deadheading is required to keep them repeat blooming for months. With few pests or problems, New Guinea impatiens offer low maintenance and high performance.

  • Leaves: Glossy, dark green, burgundy, or variegated, pointed, oblong leaves. The leaves stay attractive throughout the season.
  • Flowers: The flowers are similar, but larger than the flowers of common impatiens and they come in just about every color but true blue. New varieties are introduced yearly.

Botanical Name

Impatiens hawkeri

Common Name

New Guinea Impatiens

Hardiness Zones

New Guinea impatiens are tropical plants that are only hardy in USDA Zones 10 – 11. Most gardeners grow them as an annual plant.

Sun Exposure

Sun exposure depends on how hot it is and how much moisture the plants receive. New Guinea impatiens do best in at least a half day of full sun. If the soil is dry or temperatures are extreme, they will need up to a half day of shade.

Mature Plant Size

These are low, clump-forming plants that grow about 12 - 18 inches tall and spread 6 - 9 inches wide.

Bloom Period

Expect your New Guinea impatiens to start blooming early in the season, if they aren't already in bloom when you buy them. They will bloom continuously if they are getting enough sun and water.

Tips for Growing New Guinea Impatiens

Soil: New Guinea impatiens like a slightly acidic soil pH in the range of 6.0 - 6.5, but they are not terribly particular about it. They will need a well-draining soil, that holds moisture long enough for the roots to soak it up. New Guinea impatiens are not drought tolerant, but you don't want them sitting in wet soil for long periods or their crowns could rot.

Starting from Seed: Since New Guinea impatiens are hybrids, most varieties cannot be grown from seed. They are either sterile or will not grow true to seed. However there are a few that have stabilized, and seed is available if you want to give them a try. Luckily plants and seedlings are readily available and there is much more variety if you purchase them as seedlings. You could even bring them inside for the winter, as houseplants. They are also easily grown from cuttings.

Planting: Do not plant outside until all danger of frost has passed.

New Guinea impatiens are heavy feeders, so add a good amount of organic matter to the soil at planting time or before. Plant at the same level they are in their pots. Once in the ground, give them a good drink of water, to help them establish.

Caring for New Guinea Impatiens

Water: These plants need regular water. Do not let them remain dry for extended periods or they will stop blooming, decline, and potentially die.

Fertilizer: Since New Guinea impatiens bloom their little hearts out all season, they will need some supplemental fertilizer. Give them a dose of your favorite water-soluble food every 3 - 4 weeks.

Ongoing Care: Except for water and food, there really is no maintenance needed. You should keep the area weeded, so there is less competition for water, but that's about it. They will require a bit more care and feeding when grown as perennials or houseplants. Don't expect them to be as lush or to flower as profusely in the short days of winter.

Pests and Problems of New Guinea Impatiens

Unlike common impatiens, New Guinea impatiens are not affected by downy mildew. They should grow virtually pest free when grown as annuals.

Design Tips

New Guinea impatiens make wonderful container plants. Having them in pots lets you get an eye level view. They are also terrific for edging a walkway or the front of a border. If you want to mix it into your border, plant them in a large block, for impact.

The Best Varieties of New Guinea Impatiens to Grow

It's hard to recommend varieties for annuals that are constantly being hybridized. You never know if this year's introduction will be available again next year or if there will be an even better, improved version of it.

However, if you'd like to grow your New Guinea impatiens from seed, the Divine Series is readily available in single colors or mixes and it comes in shades of white, pink, lavender, orange, and red.