Why plant Audubon® Native Smooth Alder?
A soggy, neglected part of your property becomes a bird oasis with Smooth Alder! This moisture-loving native tree plays a key role in wetland habitats. Its vigorous root system stabilizes the soil, and its seeds, buds, and catkins (male flowers) provide nourishment to a variety of songbirds, such as pine siskins, goldfinches, sparrows, redpolls, and crossbills. Gamebirds like ruffed grouse and woodcocks also feed on the seeds. In addition, insectivorous birds seek out Alders for the vast array of insects—especially moth caterpillars—that the foliage supports. This includes backyard beauties like bluebirds, chickadees, wrens, and warblers.
If you see an Alder in the wild, it’s safe to say that you’re almost certainly near water. Smooth Alder, a.k.a. Tag Alder, a.k.a. Hazel Alder, is no exception. This North American native is never far from streams or swamps, often growing with its roots completely submerged. Like Birches, to which they are related, most Alders prefer cool-summer climates, but Smooth Alder is more adaptable. Its native range stretches from Maine to Florida and then wraps around to East Texas. Look for it in February or March, when the dangling, rusty-red and yellow catkins elongate, signaling that spring is just around the corner.
How to use Audubon® Native Smooth Alder in the landscape?
A patch of Alders is where you may find a strange little butterfly called the harvester. This pretty, orange, black, and chestnut butterfly is unusual, because its caterpillars are carnivorous! They eat woolly aphids, which they find on Alder leaves. Adult harvesters don’t visit flowers, so they’re rarely seen in gardens. They prefer tree sap, mud puddles, and dung.
Hardiness Zone: 4-9
How To Plant Audubon® Native Smooth Alder
Smooth Alder is easy to grow in full sun or part shade, as long as plenty of water can be supplied. It will need little supplemental fertilizer, as Alders have the special ability to “fix” nitrogen, or take it directly from the air. In fact, too much fertilizer can harm the microorganisms that enable the plant to do this feat. In time, Smooth Alder may form a thicket, providing good cover for birds. If you’d rather grow it as a tree, you can do so by removing suckers when they appear. In that case, it will grow much taller.
How To Fertilize
Incorporate Elements Starter Plant food granular form into the soil when planting. If planting in spring or summer, start fertilizing late fall using Elements Starter Plant food granular form on an annual basis each late fall. Continue this for the first three years to get your plant well established.