LIGHT – The Electromagnetic Spectrum

The electromagnetic spectrum ranges from low frequency, low energy radio waves to high frequency, high energy gamma rays. The human eye however, only perceives visible light.  This lies in a narrow range from around 380 nm to 780 nm of the spectrum. Interestingly enough, this visible light is continuous!  In other words, it has no clear boundaries between one color and the next.



We see in natural white light but only a small part of its spectrum wavelengths. Specifically between violet and red.





Insects on the other hand see some colors but more importantly – they can also see objects in ultraviolet light – something we can’t.


Sample picture of a flower as humans and insects see it.

Notice the white band surrounding the center and focusing direction.


Pollination and evolution

So of course….. evolution sets in motion and flowers which get pollinated by insects go on the UV rampage ! We  see the flower below as yellow – but check out how a bee sees it !


These plants produce patterns or distinct areas in their flowers that can only be seen in UV. Why? – Well to help guide the insect of course – like landing lights on a runway or a bulls eye on a dart game.



The UV area (stripes) is a way of directing and insect to land in a specific spot or area.

The spot with the pollen of course!

And some when seen under UV light – have a fluorescent sparkly GLOW!



Much of the research is currently being done at Imperial College London, and Queen Mary University in London.  They have created a database you can check out if you like.

Ctrl / click Floral Reflectance Database (FReD)



You can also go to a fantastic website with lots of pictures created by world renown UV photographer Bjorn Rorslett !

Flowers in Ultraviolet – Arranged by Plant Family –



Or you could buy a camera and see the world that way !

If you wants lots of flowers (UV or not) in your garden

call Plant Specialists today !







Article written by our Staff Horticulturist, Peter B Morris, BSc, MSc, MBA

All photographs used with permission @SHUTTERSTOCK