What Happened to My Impatiens?

Species

• Common garden annuals include impatiens (I. wallerina), New Guinea impatiens ( I.hawkeri var. New Guinea) and garden balsam (I. balsamina), all plants descended from natives of southeast Asia's cool, moist mountain forest climates. New Guinea impatiens offer the American garden greater range of color and foliage and are more suited to temperate summer heat and sun.

  Single stemmed garden balsam grows in sunny old-fashioned gardens. Orchid-like flowers bloom under leaves all along their stems and seeds develop in pods that pop open, re-seeding plants freely and giving them their old-fashioned name "touch-me-nots."

Dehydration

• Shade-loving impatiens rely on water to fuel their fast-growing branches and flowers; break a branch and it often drips. In hot or dry weather, lack of water causes collapse of plant tissue, often resulting in drooping branches or even a plant that crumples. Unless some other cause or garden pest is at work, the remedy for drooping is deep watering.

  In some areas, such as South Florida, gardeners are cautioned to wait to plant impatiens until fall for bloom throughout winter's cooler months. New Guinea impatiens are less tender but balsam that lacks hydration resembles a drooping branch as its blossom-heavy top arches over toward the ground.

Pests

• Deer often damage impatiens according to Rutgers University's New Jersey Agricultural Experiment Station and tender plants may provide a source of water for other animals like voles and squirrels during dry spells. Scale, spider mites and aphids are all "sucking insects" that can weaken branches and leaves. Fortunately, unless the pest is a deer or squirrel that rips the plant out by its roots, fast-growing impatiens are quick to recover.

Damping Off

• Early season failure of impatiens may be due to damping off, a condition that causes plants to shrivel near soil level, that may result from soil pathogens or growing conditions. Pathogens are dangerous organisms that include fungi like fusarium wilt. Seeds planted too deeply or seedlings transplanted into cold, wet soil easily succumb to pathogens. Well-drained soil stays moist but water pools around roots because of heavy clay soil or shallow cultivation.

  Plants grow slowly, flower sparsely and eventually fade or succumb to root rot, causing the plant to topple over as if it had been caught in a heavy frost. Plant tender impatiens only after all threat of frost has passed -- late frosts cause death by dehydration. Digestion of pathogens by beneficial organisms is not complete in green products, so use only well-rotted manure and compost.