Ornamental · Balsaminaceae
Impatiens
Impatiens walleriana
Hand impatiens shade and consistent moisture and it erupts with color across a shaded planting all season.
Partial shade
59–75°F · 15–24°C
60–90 days
USDA 10–11
Overview
Point impatiens at a shady spot and watch it do what almost no other flower can. This tender perennial from East Africa grows nearly everywhere as a warm season annual, packing beds, borders, and pots with bloom from late spring until the first frost. While most flowers stall without sun, this one takes off in the partial to full shade under trees and along the north side of a house.
It picked up the nickname Busy Lizzie because it just keeps flowering, working away with almost no fuss and asking only for moist soil and a break from the hot afternoon sun. The plants stay low and mounded, running 6 to 24 inches (15 to 61 cm) tall and spreading about as wide, so drop a few in and they race together into a solid sheet of color.
One thing keeps the classic seed impatiens on its toes: a disease called downy mildew that tore through gardens and turned the old favorites into a gamble. The winning move is to reach for newer resistant varieties, which is exactly why a name like Beacon matters when you pick what to plant.
Care
The short version: drop impatiens into partial to full shade, keep the soil evenly moist, feed monthly, and pull off spent blooms to keep the flowers rolling.
Light
Impatiens are shade plants to the core, hitting their stride in partial to full shade where they bloom without burning. Hot, direct sun scorches the leaves and drops the whole plant into a wilt, so hand it the dappled light under trees or a north-facing spot and let it run.
Water
Keep the soil consistently moist, because impatiens wilt fast the second they dry out, though they usually spring back once you water them. Aim the water at the base, not over the top, since wet foliage rolls out the welcome mat for downy mildew and gray mold. In heavy, poorly drained soil, ease off, because soggy roots rot.
Soil
Set them in fertile, organically rich ground that holds moisture yet still drains freely. Work in some compost and you hand the roots the steady, even dampness these plants thrive on.
Temperature
Impatiens like it mild, right between 59°F and 75°F (15°C to 24°C). They are tender and frost takes them out, so wait for warm, settled weather before you send plants outside.
Humidity
Everyday outdoor humidity keeps them happy, so skip chasing a number. What really counts is airflow, since crowded, stagnant plantings trap the damp that downy mildew and gray mold need to get going.
Feeding
Feed monthly through the growing season with a balanced fertilizer, or a weaker liquid feed a bit more often, and keep in mind that plants in pots burn through it faster. Ease up on the nitrogen, which pushes soft growth that aphids pile onto.
Pruning
Deadhead the spent flowers to keep fresh buds firing, and snip off any damaged or diseased growth the moment you spot it. That quick bit of upkeep keeps the plant blooming and the air moving.
Size & spacing
Plants climb to 6 to 24 inches (15 to 61 cm) tall and spread about the same, so give each one room to bulk up. That gap lets air move between them, which keeps disease at bay.
When to plant
Impatiens want nothing to do with frost, so hold off on moving them outdoors. Start seed indoors in late winter, set the plants out once the last frost is behind you and the soil has warmed, and you get bloom from late spring right to the first fall frost.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: 8 to 10 weeks before the last spring frost
- Plant: After the last spring frost once soil has warmed
- Harvest: Late spring to the first fall frost
Hardiness
USDA hardiness zones: 10–11
Temperature: down to -1°C
Troubleshooting
Most impatiens trouble breaks out on the leaves first, whether it is disease in damp weather or pests in dry heat. Catch the signs early and you can jump in before a small problem takes the whole planting. Match what you see below, then move while it still turns things around.
Curling, yellowed leaves crashing down to naked stems
This one is impatiens downy mildew, the disease that knocked bedding impatiens out of gardens across much of the country. Leaves turn yellow and curl down, white fuzz coats their undersides, and within days the whole plant sheds its foliage and stands as bare stems. You can't rescue an infected plant, so pull it, bag it, and keep it far from the compost.
Fix:
- Remove and bag infected plants including fallen leaves and do not compost them
- Note that fungicides cannot cure infected plants and only protectant fungicides slow spread
- Replant with resistant types such as Beacon or Imara XDR, New Guinea impatiens or SunPatiens, or switch to begonia, coleus, or caladium
Speckled, bronzing leaves and webbing when heat climbs
Fine speckling and a bronze cast on the leaves flag spider mites, which surge when the air turns hot and dry. Tap a leaf over white paper and you will catch the specks crawling. Rinse the foliage, crank up the humidity around the plant, and treat with insecticidal soap or horticultural oil on the schedule the label sets.
Fix:
- Rinse foliage and raise humidity
- Apply insecticidal soap or horticultural oil, repeating as directed
Gray mold fuzzing over faded blooms in the damp
Botrytis blight, the gray mold, moves onto spent flowers and soft tissue the moment the weather turns cool and damp. A light gray, cobweb-like fuzz races from dying blooms onto leaves and stems. Snap off the faded flowers and rotted parts, open the planting up for airflow, and keep water off the foliage to shut it down.
Fix:
- Remove spent flowers and affected tissue
- Improve air circulation and avoid wetting foliage
Sticky shoot tips swarming with minute insects
Spot clusters on the fresh shoots and you have caught aphids in the act, with sticky honeydew as the tell. They twist the young leaves around but rarely leave real damage. Hit them with a sharp jet of water to knock them loose, then chase any holdouts with insecticidal soap or horticultural oil.
Fix:
- Dislodge them with a strong jet of water
- Apply insecticidal soap or horticultural oil as needed
Toxicity
Great news for anyone with pets or kids: impatiens is safe. The ASPCA lists it as non-toxic to cats, dogs, and horses, and it poses no poisoning risk to the other common household animals or to people. Plant it right where pets graze and children play and simply enjoy the show.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Cats can share the space with zero worry, since a curious nibble on the leaves or flowers won't poison them.
Dogs None
No toxins here at all, so dogs are clear to hang around it. A chewed stem might spark a mild, passing stomach upset, but that goes for almost any plant.
Horses None
It lands on the non-toxic list for horses, so a grazing horse has nothing to fear from it.
Rabbits Safe
Rabbits can browse the foliage without harm, and some keepers even grow impatiens as a safe nibble for them.
Livestock Safe
Goats, sheep, and cattle run no poisoning risk from it.
Birds Safe
Pet and backyard birds stay perfectly safe around the plant and its flowers.
People Safe
It won't poison people, and the flowers even turn up as a garnish now and then. Still, it is an ornamental and not a food crop, so don't make a meal of it.
Varieties
Hundreds of impatiens have rolled through the trade, but a few names really earn their keep, above all the ones bred to shrug off downy mildew.
Super Elfin
This early, compact seed series packs a huge color range, but plant it knowing that, like most older Impatiens walleriana, it drops fast to downy mildew.
Beacon
This is the one that changes the game: bred for strong resistance to impatiens downy mildew, it lets you grow seed impatiens again right where the disease had shut them out.
Double-flowered (rosebud) types
Go for these when you want full, rose-like double blooms that trade the usual flat, five-petaled single flowers for something much showier.
How to propagate
Impatiens practically beg to be multiplied, whether you kick off a packet of seed indoors in late winter or snap quick cuttings from a plant you already love.
SeedModerate
Sow indoors 8 to 10 weeks before the last spring frost · Germinates in about 1 to 3 weeks; flowers roughly 10 to 13 weeks after sowing
Fire up a seed tray indoors 8 to 10 weeks before your last spring frost and you are off. Press the seed onto the surface and leave it uncovered, since impatiens need light to sprout, then keep the mix warm at around 75°F (24°C) and humid to push them along. Sprouts break through in 1 to 3 weeks, and flowers arrive roughly 10 to 13 weeks after sowing.
Stem cuttingsEasy
Spring through summer · Roots in about 1 to 2 weeks
Grab tip cuttings spring through summer and watch them root almost on their own, striking in 1 to 2 weeks in a glass of water or a pot of moist mix. It is the fun, reliable way to carry a favorite plant straight through winter indoors. Just take those cuttings from healthy stock that shows zero sign of downy mildew.
Myths
Impatiens need full sun to bloom well.
Flip that idea on its head. Impatiens walleriana is a shade plant that flowers best in partial to full shade, and hot, direct sun only scorches the leaves and leaves it wilting.
Hit infected impatiens with fungicide and downy mildew clears right up.
A fungicide only shields plants that are still healthy and cannot cure one already infected, which has to come out. The smart move is to replant with resistant varieties and keep the color coming.