Obviously, most plant leaves reflect green.  To attract pollinators (birds and insects), many plant flowers reflect a larger variety of colors (except green) to attract attention.  Some birds and insets can see near-purple ultraviolet, and plants have evolved to reflect ultraviolet light also, in order to use this "color" to attract pollinators.  Because we are ultraviolet-blind, I am showing ultraviolet intensity of various flowers as shades of white in a black-and-white rendition of an ultraviolet-only (320-380 nm) photograph.

 

The first two images are sliders of my currently-favorite pictures.  The remainder are left-to-right (those on desktops or laptops) or up-and-down (those on mobile devices or with smaller screens) for simple comparison.  Full color (visible light) images are on the left or top, while ultraviolet images are shown in black-and-white on the right or bottom.

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Nearly all plants that employ ultraviolet reflectance to attract insects will illuminate the far edges of their petals.  Some petals will not reflect UV close to the middle of the flower; this may attract pollinators to the pollen-containing part of the plant.  Note that there is no correlation between a particular visible color and the presence of ultraviolet reflectance.

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These images are taken with a Nikon 1 J5 camera, a 18.5mm F1.8 lens or a 10-30mm F4-5.6 lens (Please calculate a 2.7x crop factor for 35 mm equivalency for both lenses) taken at about 1/2000 s (full-color, with a BG40 vis-pass filter) or about 1/60 s (UV color, with a U340 + BG40 stacked filters), ISO about 1600, taken at ~f/4.  All shots are hand-held, and taken with ambient light (which in Florida when it is not raining, is pretty damn strong!).  The only Photoshopping was for color-correction for full color images if the BG39 filter was used (it has a significant blue-shift due to intentionally poor red pass-through), or intensity-boosting for UV-B&W imaging.

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