How to Grow Impatiens

Cheery, shade-loving impatiens (Impatiens spp.) liven hard-to-plant shady garden beds with their bright, pansy-like flowers. Two varieties are commonly grown in gardens: garden impatiens (Impatiens walleriana) and New Guinea impatiens (Impatiens hawkeri), which are prized for their foliage as well as their flowers. Impatiens thrive with little hands-on care, making them a rewarding choice for beginner gardeners. They must be grown under the right conditions, however, to reach their full potential.

Many gardeners grow impatiens as annuals, which means they allow the plants to die back with the first frost in autumn and replant them the following spring. Impatiens are actually herbaceous perennials, however, meaning they will survive for many years if protected from cold temperatures.

Garden impatiens will survive in the garden year-round within U.S. Department of Agriculture plant hardiness zones 10 to 11, while New Guinea impatiens grow in USDA plant hardiness zones 10 to 12. In cooler climates, try growing impatiens in pots so they can be brought indoors during the winter.

Whether grown in the garden or in pots, all impatiens share the same growing requirements:

Light shade. Direct sun and heavy shade both diminish blooming and cause poor growth.

Organically rich, neutral soil. Impatiens need moderate to high fertility to support their intense blooming.

Abundant moisture. Impatiens are soft growers, which means they wilt easily when allowed to dry out.

Organic compost

Slow release, 13-13-13 fertilizer

Lightweight organic mulch

Prepare a bed with two to four hours of filtered sunlight each day, or one with morning and late afternoon sun exposure. New Guinea impatiens must have four to six hours of afternoon shade.

Work in 2 to 4 inches of organic compost into the top 12 to 18 inches of soil. Add 3 pounds of slow release, 13-13-13 analysis fertilizer per 100 square-feet of soil area to improve nutrient-poor soil, if necessary.

Plant impatiens in spring after all frost danger has passed and the soil has warmed to 70 degrees Fahrenheit. Plant in the morning when the day is still cool to minimize wilting, and make sure they are at the same depth as they were in their nursery pot.

Space impatiens according to their mature spread. A good rule of thumb is to space taller varieties 18 inches apart and smaller varieties 8 to 10 inches apart. Avoid overcrowding the plants because they will develop lanky stems if planted too close together.

Spread a 2- to 4-inch layer of lightweight organic mulch between the plants to conserve soil moisture. Keep the mulch from touching the base of the plants.

Water weekly if less than an inch of rain falls each week. Run water at the base of the plant until the soil feels moist in the top 6 inches. Let the soil's surface dry out slightly before watering again. Check the soil frequently during very hot weather and add water if the soil feels very dry or if the impatiens wilt.

Extra fertilizer isn’t necessary for garden-grown impatiens if their bed is amended with fertilizer and compost before planting.

Bleach

High-quality potting soil

Container with drainage holes

15-15-15 or 7-9-5 fertilizer

Choose a pot 1 1/2 times larger than the original nursery container. For example, plant a 4-inch plant in a 6-inch container, or three to four 6-inch impatiens in a larger, 14- to 16-inch pot.

Wash and disinfect the pot if it was used for other plants. Soak it in a solution of 1 part bleach and 9 parts water for five minutes, then rinse thoroughly.

Plant impatiens in rich, high-quality potting soil with fast drainage. Do not use commercial soils labelled "garden soil" or "field soil" because they does not contain the moisture content or structure impatiens require.

Position impatiens where they will receive two to four hours of filtered light each day. Indoors, keep them in a 60-degree-Fahrenheit room with partly shaded south-, west-, or east-facing windows.

Water potted impatiens whenever their soil reaches a visible state of dryness. Pour water around the base of the plant until the soil is fully saturated and excess water dribbles from the drainage holes. Do not keep the soil soggy because the plant will suffer.

Feed potted impatiens with 1/2 teaspoon of water-soluble 15-15-15 or 7-9-5 formula fertilizer dissolved in 1 gallon of water. Water with the solution once a week. Increase feeding to twice weekly if the leaves turn pale or yellowish, especially if they are grown under very bright, indirect light.

Bring potted impatiens indoors when night-time temperatures threaten to dip below 45 degrees Fahrenheit.