Earth Day is a friendly reminder to be proactive in protecting the world in which we live. There are many little things we can do to help. Growing plants responsibly and buying more locally grown foods are a plus. Since locally grown food travels less, it requires less fuel, reduces our carbon footprint on emissions and has other positive environmental effects.

What could be greener than growing soybeans?

Soybeans, commonly known as edamame, can be grown successfully in backyards. The variety "Kahala," developed by the University of Hawai'i, is well adapted for local production. This soybean is popular because of its yield and resistance to the root knot nematodes.

Soybeans are most productive when planted from March to August in well-drained soils. Direct seed soybeans into your garden or into 3- to 5-gallon containers. Space plants 3 to 4 inches apart with a row spacing of 18 inches. To minimize excessive watering, check soil moisture levels and water as needed. As plants start to fruit, irrigate them regularly and keep the soil moisture consistent. Mulch can be added around plants to minimize moisture loss and reduce weed pressure.

Fertilizer costs are on the rise, so testing your soil for available nutrients is a worthwhile investment. Recommendations derived from a soil test can help you customize your fertilizer applications. Applying fertilizers as needed may help minimize nutrient deficiencies and save money.

It's best to follow soil testing recommendations if they're available. If not, a general fertilizer such as 16-16-16 can be applied at a rate of 2 to 3 pounds per 100 square feet at planting and approximately 4 weeks later at flowering.

Soybeans are self-pollinated, so they do not require insects for pollination. They are ready to harvest approximately 65 to 70 days after planting. The pods are harvestable when most of them are full and plump. The entire plant is pulled out and harvested all at once. Yellow pods are too mature, but can be saved as a seed source for future plantings.

Chinese rose beetles, bean flies and mites are common pests of soybeans. For more information about control strategies, consult the University of Hawai'i College of Tropical Agriculture and Human Resources Master Gardener Program by calling the Pearl City Urban Garden Center, 453-6055.

Soybeans are nutritious and are one of the few plants that supply a complete source of protein. They are incorporated into many of the foods we enjoy here in Hawai'i such as tofu, natto, sprouts and those onolicious garlic edamame from Side Street Inn.