An Extension bulletin written by Scot Nelson (TPSS) and Associate Dean of Extension Kelvin Sewake, “Volcanic Emissions Injury to Plant Foliage,” was quoted and recommended in a recent Big Island Now
article, “Vog and Your Big Island Garden.”
Unfortunately, the bulletin has been all too relevant to those living in areas of the Big Island affected by the opening of the new vents on Kīlauea Volcano; links to it are also available at CTAHR’s disaster-response page and , and printed versions are being offered at Hawai‘i Island Extension offices. As the article summarizes, many plants are sensitive to vog, showing signs such as leaf yellowing, browning, or bleaching. Some of the most sensitive are beans, soybeans, broccoli, Brussels sprouts, endive, lettuce, okra, peas, Swiss chard, and turnips, while crops that are less sensitive include cabbage, celery, coffee, corn, onion, tomato, watercress, and potato. The symptoms can also be signs of other plant problems, including “root rot or stem blight, drought, phytotoxicity or damage from pesticides,” according to the bulletin, so check to make sure these aren’t the problem before treating for vog. If you do need to mitigate the effects of vog on plants, you can try to shield the plants or grow them in greenhouses, or wash them with fresh water or spray with a baking soda-and-water solution to neutralize the acidity.