Underplanting for Life Cycle Completion

Among their leaves, native trees host the caterpillars of innumerable butterflies and moths. After feeding on the leaves, many of these inhabitants spend next stage of their lives hunkered down in the leaf litter beneath the tree. They wait out the winter in the leaves, wrapped in cocoons. Some will burrow into the soil. In the spring, songbirds raise their young on the insects that live among the plants and leaves. Turtles, toads and salamanders may live in the leafy environment too, and rely on the rich habitat for food, shelter and nesting material.

Native trees and shrubs are natural members of a complex food web. If your yard is home to any of these largest of native plants you can increase their ecological role, and impact local biodiversity, by underplanting.

"Soft Landings" Make a Difference

Coined "Soft Landings" by author Heather Holm, underplanting is an important way to add critical habitat support in our landscapes. The capacity of trees to sustain the life is tied to the habitat on the ground – beneath the canopy. When native trees and shrubs are surrounded by turfgrass and mulch, the ecosystem benefits that they offer are mostly lost. Underplanting creates the right environment. An assortment of shade-loving native plants growing beneath the native trees and shrubs in your landscape, will provide superior habitat, and the best support for the life cycle completion of birds, butterflies, and more.

Underplanting Tips

An underplanting should extend out to the dripline, at least, where the tree branches end. It might extend beyond, or have an irregular shape, but the planting area will cover as much ground as possible beneath the tree.
Choose native plants. Small shrubs, groundcovers, ferns, sedges, or any native perennials for shade or partial shade can be included in the underplanting.
Avoid planting within three feet of the tree trunk to prevent damaging the roots. Plants will spread to fill this area, once established.
Take care when planting. Install small plants and use a small hand trowel to dig holes. Avoid using a shovel, and avoid digging large holes under the tree canopy.

Most Important: Leave the Leaves

With an eye on increasing biodiversity in the landscape, the value of fallen leaves and other spent plant material cannot be overlooked, or overstated. The spent material is home, shelter and foraging grounds for a community of inhabitants. It is a mulch that enriches the soil and feeds the growing plants. It regulates soil temperature. The layers of plant material reduce soil erosion and moderate the speed of water run-off and absorption. There's no need to rake the leaves out of your underplanting. Simply leave the fallen leaves in place. It might take a little longer for plants to emerge in spring, but once they do, they will thrive.

Prepare Your Site

If you already have plants growing beneath a tree or trees, remove any invasive or non-native plants and replace them with native plants. In the autumn rake any leaves into the planting area within the dripline of the tree and weigh leaves down with small branches to keep the leaves in place.

Starting from scratch? If you need to remove existing turf under a tree, use a smothering method. Because the roots and trunk are so easily damaged, you'll want to avoid digging or stripping existing turfgrass under the tree. Start the smothering process at the end of summer. Place a layer of cardboard over the entire planting area. Use leaves, branches or rocks to hold the cardboard layer in place. The following spring, remove the leaves/cardboard and start planting your native plants.

It’s also important not to create a raised bed or introduce a foreign/store bought mulch into the underplanting. The leaf litter, small branches and twigs are all that’s needed to build healthy soil. This is known as a ‘duff layer’. Duff is the optimal building block for your underplanting.

Choose Your Plants for "Soft Landings"

Native plants offer an exciting opportunity to participate in restoring and supporting biodiversity. It feels good to plant natives and experience the difference these plants make. An underplanting invites more life into your landscape, and a better solution for the ecosystem.

NATIVE WILDFLOWERS