It looked like such an attractive way to fill out a sunny corner, but when that shrubby saw palmetto (Serenoa repens) grew to its highest possible spread of 18 feet, it looked more like it was out to devour the neighborhood. Worse still, though it requires just a few minutes to plant among those “little hands,” it can take years to eliminate them. Get rid of your palmettos with a plan and plenty of patience.
Palmetto Facts
Saw palmetto and cabbage palm are North American natives. With saw palmetto, waxy, fan-shaped leaves sit atop short, stout stems that develop from under ground level, emerging as the plant ages. The enthusiasts rise from 2 to 8 feet above ground. Palmettos flower between February and April. The white flowers are followed by fruits known as drupesthat ripen throughout the summer until September and October. The plants have been fire-adapted and bloom best after fire years. Other palmettos, for example, cabbage palm (Sabal palmetto), South Carolina’s state tree, grow taller but share several features with the saw palmetto.
Managing Palmetto
Palmettos’ strong underground stems not just help them to survive flames but additionally provide starts for new plants together with the first plant. Reducing these suckers under the soil line might hold back the spread of this palmetto temporarily, but the subterranean segments of the plant will simply develop more massive, eventually forcing more growth than could be controlled. Eventually, the roots will reach out beyond the initial ring of suckers, invading the surrounding plantings with suckers. In locations where flames cleared other vegetation or where palmetto suckers have never been effectively managed, the plant can become invasive, crowding out other plants.
Options
Reducing back palmettos promotes their strong roots to spread and create more suckers; burning them just promotes flowering and production of seed the next year. Mechanical control by itself doesn’t knock out a palmetto cluster, but, paired with herbicide programs, the strategy can wear the plant out. Several herbicides are effective on saw palmetto — the University of Florida’s IFAS Extension indicates a combination of triclopyr ester and metsulfuron and Texas A&M; University’s AgriLife extension recommends a combination of metsulfuron methyl, dicamba and 2,4-D. Check with a native Master Gardener chapter or university agricultural extension for herbicide recommendations to your region.
Timing
Use a combination of cutting and herbicide to “do in” problem palmettos. Starting in spring, mow the plants as far down to the ground as possible with a brush mower before or during flowering. As plants begin growing again in late summer or early fall, apply herbicide at the suggested rate and repeat broadcast or spot applications as directed on the package. If no growth occurs the next spring, then remove the subterranean stems having a stump grinder as far below the soil’s surface since the machine reaches. If the plants begin growing again, however, the cut-and-poison cycle has to be repeated for a second year.
