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| Flowers of Orange Jewelweed (Impatiens capensis). Rowan County, North Carolina. |
Jewelweeds put on a fantastic show in the fall. They produce large stands of bright flowers at a
time when other plants are fading. We are blessed with two native species of Jewelweed (Impatiens) in Eastern North America, Impatiens capensis and Impatiens
pallida. Both species of Jewelweed are herbaceous, with translucent,
succulent stems. Their leaves are coated
with a waxy layer and water drops make jewel-like beads on the surface.
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| Beads of water on Orange Jewelweed leaves. Rowan County, North Carolina. |
Jewelweeds flower in late summer and fall. They are pollinated by hummingbirds and bees. Jewelweed flowers have a spur extending from the back of the flower with a nectary at the end of the spur. Hummingbirds seeking nectar push their beaks deep into the spur and collect pollen on their faces to take to the next flower. Bee pollinated flowers have a slightly different spur structure than those pollinated by humming birds. Hummingbird flowers have a curved spur but the bee pollinated spur turns down at a 90-degree angle. The peak of Jewelweed flowering comes as the Ruby-throated Hummingbirds (Archilocus colurbris) are beginning their migration south and need a lot of energy.
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| Orange Jewelweed flower as its pollinators see it. Rowan County, North Carolina. |
Impatiens capensis has a number of common names including Orange Jewelweed and Spotted Touch-me-not. The flowers are orange and yellow with darker spots. This annual grows in moist soil along streams, forest understories and ditches. Orange Jewelweed is used in traditional medicine to treat poison ivy, bee and nettle stings.
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| Orange Jewelweed from the side. This flower has a curved spur at the back indicating a hummingbird would be most successful pollinating this flower. Blue Ridge Parkway, Watauga County, North Carolina. |
The fruits of Orange Jewelweed are up to an inch long and have a surprising way to disperse their seeds. If you touch a mature fruit of Jewelweed it will explode in your hand, throwing seeds up to ten feet from the parent plant. This violent spreading of seeds is called ballistic seed dispersal and is powered by tension in the fruit wall. An animal brushing the plant, a raindrop or even a slight breeze will cause a shower of flying seeds. Ballistic seed dispersal is what gives this Jewelweed one its common names, Spotted Touch-me-not. It is as if the plant does not want to be touched and pops seeds in protest. When our kids were young they liked to make Jewelweed fruits explode on our mountain hikes during the fall. They came up with their own name for this plant, Poppy-heads.
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| Orange Jewelweed fruit. Rowan County, North Carolina. |
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| Isolated Orange Jewelweed fruit. The fruit wall is under tension and primed to explode. Rowan County, North Carolina. |
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| The fruit from above after exploding. Rowan County, North Carolina. |
Impatiens pallida, Yellow Jewelweed, is a close relative of Orange Jewelweed and has many of the same characteristics. The most obvious difference is flower color, which in this species is pale yellow. In our area, Yellow Jewelweed grows mainly in the mountains while Orange Jewelweed is found throughout.
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| Yellow Jewelweed (Impatiens pallida) flower viewed from the front. Blue Ridge Parkway, Watauga County, North Carolina. |
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| Yellow Jewelweed flower seen from the side. The spur on this flower is perpendicular so this flower is most likely to be pollinated by a bee. Blue Ridge Parkway, Watauga County, North Carolina. |
Jewelweeds flowers are a sign of fall. In October I found large numbers of Green Stinkbug (Chinavia hilaris) nymphs on Orange Jewelweed. These bugs lay their eggs on Jewelweed and the nymph stages develop on the plant until they molt into adults and fly away. Jewelweeds are killed by the first frost but grow again the following spring from the multitude of seeds the plants threw out.
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| Green Stink Bug (Chinavia hilaris) nymph on Orange Jewelweed. Rowan County, North Carolina. |
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| Orange Jewelweed Blue Ridge Parkway, Watauga County, North Carolina. |
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