When planting a vegetable garden, let color be your guide to healthy eating. For a number of years, scientists have been discovering the health benefits of the color pigments in food. For some gardeners, a vegetable garden is lettuce, collard, mustard greens and kale — all healthy, leafy green vegetables. But for health sake, add some color — red tomatoes, yellow squash and purple eggplant. Grow a rainbow of colors to the garden for good health.
Red colored fruits and vegetables contain natural plant pigments called lycopenes or anthocyanins. These compounds may help reduce the risk of several types of cancer, especially prostate cancer. By the way, lycopenes in cooked tomatoes with a small amount of fat are absorbed better than lycopene from raw tomatoes. Sun dried tomatoes are reported to have twelve times the lycopenes as raw ones. So plant plenty of tomatoes, beets, watermelon and red peppers. If there is room, include a pigmented citrus tree like pink grapefruit in the yard.
Orange and yellow colors come from natural plant pigments called carotenoids. Beta-carotene is converted to vitamin A which helps maintain healthy eyes. Carotenoid-rich foods can reduce the risk of cancer, heart disease and can improve immune system function. Plant plenty of yellow sweet potatoes, squash, pumpkins and carrots. Citrus contains hesperidin (also found in the skin of tomatoes) and naringenin, which are anti-inflammatory and antioxidant. Curcumin, found in turmeric, known in Hawaiian as olena, has antioxidant properties.
Turmeric is a popular Indian spice used in curries and other dishes. Anecdotal evidence suggests that turmeric can be used to deter ants in the garden. Other yellow and orange fruits grown in Hawaii are pineapples, papayas and mangos. Pineapples contain bromelain, an enzyme which aids digestion. Papaya and tangerines contain beta-cryptoxanthin, another carotenoid, playing an important role in vision and in bone growth. Papayas can easily be grown from seeds or purchased in abundance at local markets.
Greens are colored by a natural plant pigment called chlorophyll. Some greens contain lutein which helps keep eyes healthy. Plant green peppers, peas, parsley, watercress, arugula, spinach, kale and other dark leafy greens. Crucifers like broccoli, cauliflower, and cabbage contain chemicals which may help protect against some types of cancer. Since these are cool season vegetable, you may want to save these for a fall planting. Leafy greens such as spinach and broccoli are excellent sources of folate which is a B vitamin. Recently much has been written about the benefits of green tea. Tea plants can be purchased from local nurseries; plants readily grow into leafy shrubs. Young leaves of tea plants can be processed for homemade consumption.
The blue and purple colored fruits and vegetables also contain pigments called anthocyanins, powerful anti-oxidants which improve brain function and help to reduce the risk of cancer, stroke and heart disease. Spring is a good time to plant eggplant and later in the year red cabbage and purple cauliflower. Fig trees grow well in tropical and sub-tropical climates and should yield delicious, healthy fruit. Anthocyanins, also found in strawberries and raspberries, act as powerful antioxidants that protect cells from damage.
The whites contain pigments called anthoxanthins which range in color from white, or cream to yellow. This group consists of onions, garlic, cauliflower, turnips, mushrooms, potatoes and bananas. At least one of the group, garlic, contains a health-promoting chemical called allicin. This compound may help lower cholesterol and blood pressure and help reduce the risk of stomach cancer and heart disease.
Try planting some potatoes. Cut an organic potato into several pieces, each containing an ‘eye’. Allow them to dry for a few days and then place them in a loose, loamy soil. In a few months, potatoes of various sizes will materialize under the earth. Virus free potato ‘seeds’ can also be purchased from catalogs. Potatoes, as well as bananas, are good sources of potassium. Bananas grow abundantly in Hawaii.
Check out www.gardenguyhawaii.com for more information about growing various fruits and vegetables.
Reminder: vegetable gardening class this Saturday. Call 974-7664.
Hilo resident Nick Sakovich is a professor emeritus of the University of California. He has worked in the field of agriculture for 30 years, and is a member of University of Hawaii Master Gardeners. E-mail your questions to Sakovich at firstname.lastname@example.org.