Garden Impatiens Impatiens walleriana

Impatiens are one of the most popular bedding plants and one of the most common shade flowering plants in the United States. Their bright and prolific blooms of white, peach, apricot, pink, and red are present from late spring until the first frost of fall. They are technically herbaceous perennial plants in tropical zones, but they are frequently grown as annuals.  They are fast-growing, dense, mounding, or clumping in habit and grow 0.5 to 2 feet tall and equally as wide. Flowers may be bicolored, single, or double. They have 5 petals, and the leaves are oval to elliptic and light green to dark green with sometimes a bronze cast.

This plant is native to Kenya, Mozambique, Tanzania, and Zimbabwe. It is a subshrub and is found primarily in wet tropical areas.

The genus name, Impatiens, is derived from the Latin word impatiens, which means "impatient.' This references the abrupt release of seeds from the ripe seed pods in the late summer and fall.

Impatiens perform best in part shade to full shade. They may grow in partly sunny areas when they have adequate water, but too much sun may scorch the leaves. They require moist, well-drained soils, supplemented with organic material, and a slightly acidic pH.  The plants tolerate humidity, but they are sensitive to heat and appear wilted in hot, dry spells and will require extra watering. Overwatering, however, can cause the plant to rot. This plant has low drought tolerance and is hardy in zones 10 to 11. In late summer, the plants may appear leggy. To promote new blooms and improve the plant's appearance, trim off the top one-third of the plant.

Impatiens can readily self--seed. The seed pods are ripened in late summer to fall, and the seeds can be harvested. The plant can also be easily propagated from cuttings taken in the fall and replanted in the garden in the spring after the last frost has passed. Seeds may be sown indoors in late winter. It may take several months for the seeds to mature into flowering plants. Seedlings can be planted outdoors after the last spring frost.  These are tropical plants that will not tolerate cold weather. It is best to pull up the plants in the late fall and discard them or bring the potted plants indoors over the winter months.

Impatiens are often utilized in planters, hanging baskets, and containers. They are also used in mass along shady borders, under trees, or in woodland settings. Remember to consider disease-resistant varieties or cultivars for success in the garden. 

Seasons of Interest:

Bloom:  Late Spring, Summer, and Early Fall     Foliage:  Late Spring, Summer, and Early Fall

Quick ID Hints:

• Flowers have a white, conspicuous, elongated spur.
• Has a lateral sepal pair that is elongated and narrow.
• Leaves have stalked glands on teeth rising above the leaf plane.
• This succulent mounding plant has leaves that touch the ground.

Insects, Diseases, and Other Problems:  Impatiens have no serious insect or disease problems. Deer can be troublesome. Potential insect pests include aphids, nematodes, spider mites, slugs, and snails. It is susceptible to powdery mildew, downy mildew, and verticillium wilt. It is always best to purchase healthy or disease-resistant plants. Impatiens hawkeri is an alternative and is resistant to downy mildew. Downy mildew is, caused by the ‘fungus-like’ organism Plasmopara obducens. Fungicides used to control fungal diseases will not work on downy mildew.

VIDEO created by Andy Pulte for “Landscape Plant Identification, Taxonomy, and Morphology” a plant identification course offered by the Department of Plant Sciences, University of Tennessee.