An exciting benefit of gardening is the vast palate of colors that can be observed with garden plants. Vegetables, flowers, herbs and fruits contain natural pigments that can be visually seen as red, orange, yellow, green, blue, purple, white, black and brown.
The colors we find among our garden plants are the result of complicated genetic traits that are expressed over the course of the growing season. Color can even be an indicator of plant nutrition and overall plant health. Sometimes, poor color expression, like yellow or dull leaves, can be a signal for plant disease or nutrient stress. Colorful plants also attract pollinators and other beneficial insects to the garden.
The color of vegetables, flowers, herbs and fruits commonly grown in West Virginia gardens is derived primarily from pigments like chlorophyll, carotenoids and anthocyanins. These pigments are dominant in certain plant parts and can exist alone or in combinations, creating various shades of colors.
The robust green color of leafy vegetables, such as spinach, kale, collards and lettuce, is from the pigment chlorophyll, which is primarily responsible for the process of capturing light energy by photosynthesis. Green vegetables are an excellent source of many nutrients and vitamins, such as vitamins C and K.
Green leafy vegetables are also a source of antioxidants, such as carotenoids. Carotenoids, when dominant, produce distinct red, yellow and orange colors in plant organs and include important compounds, such as beta-carotene and lycopene, which are found in red tomatoes, beets, red peppers, sweet potatoes, winter squash, carrots and watermelons. Beta-carotene and lycopene can reduce certain types of cancers.
Anthocyanins produce shades of red, purple, blue and black in plants and provide nutrients that can be found in crops, such as black raspberries, purple or black tomatoes, blueberries, purple asparagus, eggplants, red cabbage, purple carrots, and blue or purple Irish potatoes.
Vegetables that lack pigments and are white, such as leeks, garlic, fennel and onions, also contain essential nutrients, such as vitamin K, calcium and antioxidants, which prevent many types of chronic diseases in humans.
Adding colorful vegetables to both the garden and your diet will have long-lasting, positive effects!
By Lewis Jett, WVU Extension Specialist – Commercial Horticulture