University of Vermont Extension
Department of Plant and Soil Science
Dr. Leonard Perry, Extension Professor
University of Vermont
busy lizzy, or touch-me-not are all names you may see for this
popular annual flower. It comes in many
flower colors, with selections for either sun or shade. A new
disease, however, is limiting the use
and sale of the shade impatiens so you may need to seek alternative
your garden gets little sun.
shade impatiens (Impatiens walleriana)
is just one of 500 species in the Balsam family or Balsaminaceae,
which includes the old-fashioned garden balsam (I. balsamina)
and the newer hybrid New
Guinea impatiens (I. hawkeri). The latter was introduced
from a plant exploration on this South Pacific
island in 1970. There are several other impatiens you may see, such
as the 3 to
4-foot tall jewelweed (I. capensis),
whose orange flowers the hummingbirds love but gardeners may hate as
name comes from the fact they are “impatient” to eject their seeds,
slightest touch will cause ripe seedpods to open and scatter seeds
to the wind.
Originally thought to be indigenous to
Zanzibar (an African island now part of Tanzania), the shade
impatiens also was
found to grow in the eastern regions of equatorial Africa. It was
the western world in 1896 by Dr. John Kirk, a renowned British
naturalist who accompanied Dr. Livingstone on many of his African
might be assumed, the shade impatiens should receive part shade
(less than 6
hours direct sun per day), and will tolerate filtered sun to full
shade. Although today's impatiens varieties are more sun-tolerant
than older varieties,
too much sun will cause impatiens to have
small leaves, few blooms, and little height. You may see these
called “bedding” impatiens
as they are commonly massed in garden beds.
impatiens can be planted under trees although special care is
needed, as the
tree roots will compete with the flowers for space, water, and
Impatiens planted here will require frequent watering and additional
fertilizer, as will mature plants in containers. One easy solution
under trees is
to construct a slightly raised garden six to eight feet from the
tree. Or you
can dig out roots, if they are some distance from the tree, and fill
with a soil mix for planting.
impatiens, such as the popular New Guinea cultivars (cultivated
grow in full sun in the north, but tolerate part shade and in the
part shade. Make sure they are kept
well-watered if in sun, but are in well-drained soil as all
impatiens like. If they do wilt, unless severely, they should
revive soon with watering.
of shade impatiens generally grow from six to eighteen inches tall,
on series, and one to two feet wide.
Size will vary, depending on the spacing, moisture, available
and amount of sunlight. Flower form can be single, semidouble, or
Guinea impatiens are generally upright with less spread. Flowers
are single but up to two times larger
than those of shade impatiens, and often in more brilliant and
colors. Their foliage is much larger,
stiffer, elliptical, and often in dark green to purplish colors.
They are generally propagated by cuttings, while
shade impatiens are generally from seeds.
New Guinea impatiens, too, can be massed in beds but also are
in fronts of beds, along walks, and in containers.’
are often found in a named “series”, having up to two dozen or more
color choices in each. Examples of shorter
series of the shade impatiens with single flowers include Accent,
Carnival, Dazzler, Infinity, Super
Elfin, and Swirl. Series on the taller side with single flowers
Shady Lady, and Tempo. Taller series
with double flowers include Cameo, Carousel, Confection, and Fiesta.
popular series of New Guinea impatiens, again in many colors but not
choices as with shade impatiens, include Celebrate, Gem, Harmony,
Impressions, Ovation, Paradise, Petticoat, Pizzazz, Pretty Girl,
and Riviera. There are several named
cultivars not in series, such as the orange-flowered Tango—an
Selections winner in 1989, and one of the first to be grown from
starting impatiens from seed, sow indoors 8 to 10 weeks prior to
outdoors after the last frost. “Harden off” seedlings before
outdoors, putting them out in part shade and bringing them in on
frosty nights. If buying plants in spring, choose ones that
aren’t wilted or showing signs of stress, with good leaf color, and
remember that the more tightly they are spaced, the taller they will
fill in sooner if closely spaced, but you’ll need more plants. For
example, if plants are used for a border,
space them eight to 12 inches apart so they will spread but remain
low growing. Mix in compost before transplanting,
especially if a sandy or clay soil.
you want to grow impatiens in window boxes or other containers, use
a sterile or
soil-less growing mixture rather than garden soil to allow for
Space according to the height you wish the plants to attain.
container plants will need more frequent watering than plants grown
thoroughly after planting, and continue to water throughout the
if it doesn’t rain. Keep soil moist, but avoid overwatering as this
encourage fungal diseases. Avoid overhead watering late in the day
foliage will not have sufficient time to dry before nightfall and
will be more
prone to disease. Fertilize impatiens
frequently, according to label
directions on your product of choice.
couple of less serious impatiens problems for most include a virus
fungus. Impatiens necrotic spot virus is
carried between plants by the tiny thrips insect, and may cause
stunting, ringspots on leaves, or brown to purple
spots on leaves and stems. Unless
severe, plants usually live. If plants
are too wet or with insufficient space and air movement, they may
rhizoctonia crown rot. This fungus may
cause yellowing, wilting, and plant collapse.
Prevent it with proper culture, and neem oil sprays if the disease
worst disease and a new one, with no good controls nor fungicides
gardeners, is fortunately a problem just on the shade impatiens.
Impatiens downy mildew has spread widely in
the plant industry, and is the reason many growers have stopped
impatiens. Unique to this plant species, it is different from downy
other plants. Symptoms begin with leaves
slightly curling downward, yellowing, then growth becoming stunted.
A white downy coating can be seen on
undersides of leaves. Plants can soon
drop all leaves and flowers and collapse.
avoid impatiens downy mildew, inspect plants before purchase. Don’t
plant where you had impatiens die from
this previously. Use good culture and
plant spacing. If impatiens are
infected, remove plants as the disease can live on the dead debris.
Throw infected plants in the trash, not the
compost. You can start plants from seeds, as these don’t carry the
disease. The SunPatiens brand has shown
high resistance to this disease. Or, alternative plants you may
consider are caladium,
coleus, begonias (there is a huge range of these to choose from),
torenia, polka-dot plant, and New Guinea impatiens.