Water Elm

Size, growth and what to expect

Water elm grows slowly, about a foot a year in our growth estimator. It makes a small tree of 30 to 40 feet with a short trunk and a low, broad crown, often on several stems.

The small green flowers open with the leaves from March into May, and the warty fruit ripens in spring. The fruit is a leathery nut about half an inch long, covered with warty, burr-like projections, and waterfowl eat it. The gray-brown bark flakes away in patches that show red beneath.

It grows wild on the coastal plain from southeast North Carolina and north Florida to east Texas, and north in the Mississippi Valley to southern Illinois. It lives in swamps, along streams and lakes and on floodplains, often in large stands. In wet ground its roots flare into flattened buttresses.

How to grow Water Elm

Water elm wants full sun or part shade and a wet, sandy or gravelly soil, and it takes standing water. Acid or neutral soil suits it. Keep it out of dry ground, since it tolerates little drought. Plant it 15 feet from a wall and at least 15 feet from overhead wires, and set trees 25 feet apart.

Saplings ship bare-root or potted. Plant them dormant, from leaf fall until bud swell, in a hole wider than the roots and no deeper. Set the root flare at the soil line, put the native soil back in, and keep the mulch clear of the trunk. The seed needs no chilling. Sow the warty fruits fresh, as soon as they ripen in spring, and keep the bed moist until the seedlings are up.

Water weekly through the first summer unless the ground stays wet. Deer rarely browse it, but a tube guards the stem where they are many. Let it grow on several stems as it does in the wild, or choose one trunk early.

Male and female flowers grow on the same tree, with a few that carry both parts, so there are no male and female trees to pair. NC State Extension lists it as resistant to Dutch elm disease, which with phloem necrosis has killed most of the elms of North America since the 1930s.