Caring for Impatiens
Impatiens plants are one of the most popular annual flowers, due to their brightly colored blooms and their ability to grow in shady areas. Although technically tropical perennials, these plants are grown as annuals in all but the warmest regions (zones 10 to 12). The Impatiens genus—one of two genera in the Balsam family of plants—has many dozens of species, two of which are common garden plants. Impatiens flowers take their name from the Latin, impatiens, meaning “impatient.” They are so-called because their ripe seed pods will sometimes burst open from even a light touch (as if they were impatient to open).
Impatiens are easy to grow in any moist, well-drained soil in a shady or semi-shady location. New Guinea impatiens will tolerate more sun than do standard impatiens. In northern United States and areas with similarly cold winters, the traditional time for planting impatiens is Memorial Day, when the danger of frost has passed. If planted in soil that is too cold, these plants will languish for the entire growing season. After planting, pinching back the stems will encourage bushier growth.
While the plant is quite popular, don’t let the claim that this plant is “overused” hold too much sway over your buying decisions. If a particular color of impatiens helps fill a need in a flower border or anywhere else, especially in shaded areas, you are well-advised to use it.
With sufficient water impatiens can be grown in a part-sun location in northerly regions, their great virtue is that they thrive in the shade. In fact, they’re among the relatively few readily available, inexpensive flowering plants that will put on a great floral display even when grown in full shade. The New Guinea forms are much more tolerant of sun and can even thrive in full sun if watered frequently.
Grow impatiens flowers in well-drained soil enriched with organic material. The soil must drain well to avoid becoming boggy from the frequent watering that impatiens require.
Once in the ground, the impatiens will need at least two inches of water a week. When temperatures average consistently above 80 degrees, water at least four inches weekly. In window boxes and hanging pots, impatiens may need watering daily.
Temperature and Humidity
Impatiens are quite sensitive to heat. If your temperatures rise above 85 F, they will require at least four inches of water per week. Container impatiens will need daily watering—or twice daily if temperatures are above 85 degrees. If there has been a long, dry spell, your plants will likely look wilted. Thankfully, they bounce back quickly. Give them some water and they will perk back up.
Impatiens are tropical plants that will turn to mush at the first light frost. Bring them indoors if you plan to keep them over the colder months. They are fine in humid weather.
Impatiens will flower best if regularly fertilized. A water-soluble fertilizer can be used every two weeks throughout the spring and summer. Another option is a slow-release fertilizer used at the beginning of the spring and again halfway through the summer. If your impatiens plants start looking leggy late in the summer, use scissors to trim off the top one-third of their vegetation. This will promote the emergence of new blooms and improve the overall appearance of the plants. One possible cause of legginess is over-fertilization.
Common Pests & Diseases
Aside from the downy mildew that devastated the standard impatiens, these plants can be affected by viruses, fungal blights, and rots. These problems are more likely in humid, wet conditions or where plants are crowded together too closely.
Insect problems include aphids, mealybugs, thrips, whitefly, slugs, snails and spider mites. Severely affected plants can be removed. Minor infestations can be treated with horticultural oils or pesticides.
Too much sun may scorch the leaves on most varieties of impatiens, though the New Guinea varieties can usually tolerate full sun if given extra moisture.
Information courtesy of TheSpruce.com