Summer is here and the flowers have burst forth with a razzle dazzle of rainbow colors. There are zinnias of white, yellow, orange and blazing red. There are forget me nots as blue as the sky and pansies like purple velvet. It seems unfair to explain all this in the matter¬of fact terms of chemistry. But chemistry too is full of aai,',zing wonders and the fascinating expla.n ation of flower colors actually adds to our appreciation of the glories in the garden.
It seems reasonable to expect each type of flower to have its own color, ,just as it has a certain shape and perfume. We tend to expect lilies to be white and violets to be blue. But there are pink and yellow lilies and sometimes violets are white. These color variations depend upon certain complex chemicals which are present inside the plants.
The most common of these pigment chemicals is chloroplal, which may be blue green or yellow green. Chemicals called carotinoids are pigments which can tint flower petals many colors ranging from Dale yellow to orange red. Zinnias and sunflowers owe their colors to the carotinoid chemicals.
A group of chemicals called anthocyanins are responsible for a variety of flower colors ranging from red, through blues to purples. The velvet pansies and the dainty forget me nots owe their colors to the anthocyanin chemicals.
In some flowers green chlorophyll is present along with yollow carotinoid chemicals. The green may be hidden or masked by the yellow, or it may add a different tinge to the flower color. Different colors in the same variety of flower may result from a difference in the proportion of chlorophyll and carotinoid.
Some flowers contain two or more pigment chemicals and the result is a blending of colors.
A plant makes its pigments from sugar and chemicals in the soil. Light and sometimes temperature play a part in the recipes. The necessary ingredients may be scarce or plentiful and this will effect the quality and the amount of pigment chemical. Hydrangea flowers grown in certain acid soils tend to be blue and pink when grown in certain alkaline soils. This is because certain soil chemical; are used in the manufacture of the anthocyanin pigments.
Plants, like people, tend to inherit features from their parents. They also inherit features from countless ancestors. A red zinnia is likely to have red offspring, but a certain proportion of these offspring will resemble their yellow or orange ancestors.