Home » Gardening » Treating diseases and pests » Problems with sunpatiens? Possible diseases and pests

Problems with sunpatiens? Possible diseases and pests

Sunpatiens problems

Sunpatiens is a type of impatiens bred to resist most diseases. However, it still occasionally falls sick and has to deal with pests!

More about sunpatiens:

Pests on Sunpatiens

Tiny bugs on sunpatiens

Although generally not so vulnerable to diseases and parasites, occasionally you’ll notice an invasion of red spider mites, thrips or aphids on your impatiens.

Shown here is the pumpkin beetle, which is quite harmless for sunpatiens.

A good way to get rid of all three is to hose the plant down with a nozzle. Test it on a small portion first to adjust the strength of the spray: Sunpatiens leaves and stems are softer than those of most other plants! A spray that is too strong will rip leaves off from the plant.

Holes on leaves on sunpatiens

If holes appear on the leaves of your sunpatiens ®, be on the lookout for slugs because they love this type of plant and you must act fast.

Sunpatiens leaves disappearing, eaten off

If you notice leaves disappearing entirely, there might be a few caterpillars hiding underneath.

Caterpillar on sunpatiensImpatiens hawk moth (or hawkmoth) is a caterpillar that favors plants of the Impatiens family. It is normally only active in SouthEast Asia, from India to the Philippines (including Australia and Indonesia). This pest also feeds on Fuchsia and Zantedeshia.

Diseases that infect sunpatiens

Unlike common Impatiens, Sunpatiens ® lineage was selected and bred to resist downy mildew. That’s what usually kills impatiens flowers, but Sunpatiens is immune to it!

Sunpatiens rotting roots and stems

Although it comes from Impatiens varieties that were resistant to most types of diseases, a Sunpatiens plant may contract certain root rot fungus when growing conditions aren’t ideal. Different molds or fungus infect the flower, especially if weakened by lack of water. These include common soil pathogens such as Rhizoctonia and Pythium.

Brown spots on Sunpatiens petals

Young, freshly planted Sunpatiens might contract a disease caused by gray mold, Botrytis cinerea. This is a type of mold that breaks organic matter down. Sunpatiens flower petals are thin and fragile, they’re more easily infected than other parts of the plant.

spots on sunpatiens leavesSymptoms for Botrytis blight are spots on flower petals:

  • spots are irregular and form large blotches on leaves,
  • spot colors are either brown or tan.

To counter this blight:

  • remove infected flowers and leaves,
  • increase access to light and air by pruning or spacing your plants
  • replace plant mulch by mineral mulch to reduce the amount of rotting matter around the young flowers.

Sunpatiens too hot or freezing

Sunpatiens in the cold

The coldest temperature a Sunpatiens plant can survive is 32°F (0°C), and then only for a couple hours. This plant doesn’t have any coping against freezing. Cells burst when water inside them turns to ice, even for just an hour of morning frost. Winterize the plant diligently to protect it from the cold.

Symptoms of freezing include :

  • burst stems go limp
  • after a few days, they turn dark green, then brown and mushy.

Wilting Sunpatiens in full heat

Wilting sunpatiensVery hot weather, above 100°F (37°C), will result in wilting at the hottest hours. This may happen even if you provide constant water through drip irrigation.

  • Irrigate to help the plant survive this heat.
  • Blooming is impaired and flowers wilt much faster.
  • As soon as temperatures drop back to normal, blooming resumes in full.

The wilting is a symptom of light water stress. This stress diverts energy to the root system to expand and strengthen it. Having the habit of only watering when you notice that slight wilt is the best thing you can do for your sunpatiens!

Impatiens naturally evolved as a shade plant. Although sunpatiens is derived from impatiens, it’s astounding to see this hybrid easily thrive in such full sun and hot temperatures!

Leaf scorch

In regions where the air is very dry and hot, your sunpatiens might be vulnerable to leaf scorch. This only happens if the plant lacks water for more than couple days. Make sure to water diligently and, if needed, set up a constant drip irrigation system.

Images: CC BY 4.0: Se Lena, N&G contributor: Joyce Gerber, Pixabay: Hartono Subagio
A comment ?

Your email address will not be published. Required fields are marked *

Your reactions
  • Bill Beattie wrote on 25 March 2023 at 23 h 16 min

    I have raised these in large, well drained containers for 3 years.
    Every year several plants get some
    disease that causes them to get gnarly and stop blooming.
    Would appreciate suggestions on what to apply to prevent this disease.

    • Gaspard wrote on 27 March 2023 at 2 h 50 min

      Hi Bill,
      gnarly leaves are often a sign of either some type of leaf curl, or an infestation of tiny bugs. Are there any aphids, scale insects, or mites? Sometimes they’re quite small and you need a magnifying glass to see them.

      To get rid of them, a good first step is to spray leaves with water. Put a little force on the water to dislodge them, but not too much so the leaves aren’t ripped off.

      Other options are described here: aphids, scale, mites. They describe many different products and tips to deal with these pests.

      There is a chance that your sunpatiens is diseased, but for that it’s really important to have good pictures. If a plant is dying out, try including a picture of its roots, too.