Can plants be colors other than green?
Even Earth has a diversity of photosynthetic organisms besides green plants. Some land plants have red leaves, and underwater algae and photosynthetic bacteria come in a rainbow of colors. Purple bacteria soak up solar infrared radiation as well as visible light.
Plant leaves and stems aren't always green because they have many pigments other than chlorophyll. Pigments are molecules that absorb specific colors of light and reflect other colors, depending on their chemical structure. The reflected colors are what give pigments their color.
Plants of different colors contain other pigments, such as anthocyanins, which are responsible for reds and purples; anthoxanthins, which reflect yellow; and carotenoids, which reflect yellow, orange, or red. When plants change colors in autumn, it is due to their having a mixture of these pigments.
Some plants have leaves with color other than green. This Florida Sweetheart caladium-the leaves are shockingly pink. A clear pink. The color possibilities that this plant enables in a shady spot are many.
There are no trees with blue leaves. However, some characteristics may make the green leaves appear blue. The blue spruce and the blue atlas cedar are the two most common trees with leaves that appear bluish-white.
We have virtually every other color of the spectrum, but no blue. There are purple and maroon leaves, and these two color have a component of blue in them, so there is blue pigment in there somewhere. But leaves are never blue.
Most notable are flowers that change color with soil pH. Specific species of hydrangea are best known for having this unmistakable attribute. While hydrangeas grown in acidic soils produce brilliant true-blue blooms, more alkaline soils may result in flowers that are shades of bright pink.
The pink colorations in plants (along with purples, reds, and blacks) are caused by a group of plant pigments called anthocyanins.
Chlorophyll gives plants their green color because it does not absorb the green wavelengths of white light. That particular light wavelength is reflected from the plant, so it appears green.
All these colors are due to the mixing of varying amounts of the chlorophyll residue and other pigments in the leaf during the fall season.
Why do plants have different pigments?
Most photosynthetic organisms have a variety of different pigments, so they can absorb energy from a wide range of wavelengths.
Like humans, flowers inherit their appearance from genes. Pigments are “born” into these plants, producing a range of colors across the spectrum. The same chemical, carotenoid, that produces pigment in tomatoes and carrots, also produces yellow, red, or orange color in certain flowers.
