A tour of the Arnold Arboretum with Fred a few weeks got me thinking about trees from around the world, but now a note from a reader about great native trees and a conversation with my gardening friend Jamie in South Bend, Indiana, have me thinking about what our own woods and meadows offer for our backyards. As a bit of a plant nerd, I will most likely never restrict myself to planting only natives. However, there are many wonderful native trees and shrubs that not only are good garden performers but, because they co-evolved with the other flora and fauna of the places we inhabit, also support the local ecosystem. Over the millennia, adaptations have taken place that created symbiotic relationships between the plants and animals of the same region; these evolutionary interconnections help to guarantee their mutual survival. For example, the native white oak supports many species of birds, mammals, and insects that play a role in the pollination and well-being of our gardens and farmland, whereas a non-native Bradford pear is a virtual food desert for these same species. And, in turn, many of these creatures serve as natural predators for pests that might impact the oak’s health.
For this reason, while, as an avid plant collector, I may include a variety of non-native plants in my garden, I am always excited when I can find a native that meets my aesthetic needs. In fact, there are many plants that can fulfill my ornamental desires while also actively helping to maintain a balanced ecosystem. (I also would like to stress here that if you do choose a non-native, you must not choose one that will potentially become invasive, either by seeding or spreading aggressively, supplanting the natives in the landscape around them.)
Between the death of an old crab apple tree and the clearing of a new space at the back of his property, my friend Jamie, who gardens in South Bend (a place now held in our collective imagination because of the presidential aspirations of its mayor), saw an opportunity to go a little more native. As he and I reviewed the considerations – size, light, maintenance, and the possibility of the strip at the back serving as a hedge — we began compiling a list of the species that would work there. The options that were native varied and did not feel the least bit limited. I was particularly enthusiastic about two, the oakleaf hydrangea and blueberries, because they offered so many desirable qualities — great flowers, wonderful foliage and fall color, and, in the case of the blueberries, breakfast for Jamie and/or a number of native birds. I often think blueberries get short shrift as ornamentals, and whenever possible I try to convince people to grow them, provided they have the acid soil that blueberries require.
From there, our list went on to include hobblebush and other native viburnums as well as the often overlooked native hollies, which add winter color when their colorful fruit stand out in the winter landscape. Winterberry and American holly are underrepresented in our gardens and work well ornamentally and as forage and habitat for local wildlife. The evergreen foliage of the latter, if sited correctly, also serves as a nice screen from northern winter winds, providing our homes with much needed protection on cold winter nights. And American smoketree also came to mind as a good bet for hedging, as it can be coppiced or cut back hard each spring to keep its size in check.
As we continued on, we thought about small trees to replace the crabapple. Fringetrees and shadbush were obvious choices, particularly at a moment in the season when their flowers were fresh in our memory. Magnolia virginiana and the native large-leafed magnolias, pawpaws and spicebush also came to mind. It is funny how the words bush and tree seem interchangeable in the common names of small trees and large shrubs, making one realize that the categories we have defined for woodies are really about our own interpretation of what they are, all woody plants being equal in the eyes of Mother Nature. Essentially, they are just plants with woody stems that do not die back to the ground each winter. The back and forth banter that Jamie and I had was fast and fun, and served almost as a test for what natives we might have overlooked. Our text correspondence in the weeks that followed explored other possibilities, many of which, like the native elderberry, were evident in full flower along the roadside. A morning spent at the New England Wild Flower Society’s Garden in the Woods in Framingham, Mass., sent me texting Jamie about native rhododendrons, kalmias, strawberry shrubs, fothergilla, bottlebrush buckeye, and Carolina snowbells, each offered as a possibility worth considering. I cannot wait to see what he decides upon.
And while a walk around the Arnold several weeks ago was inspiring, it is also good to know that there are other inspirations close at hand. A simple walk through a local woods, around Bartholomew’s Cobble, or across the covered bridge in Sheffield can bring our local horticultural bounty to the forefront of our imagination.
A gardener grows through observation, experimentation, and learning from the failures, triumphs, and hard work of oneself and others. In this sense, all gardeners are self-taught, while at the same time intrinsically connected to a tradition and a community that finds satisfaction through working the soil and sharing experiences with one another. This column explores those relationships and how we learn about the world around us from plants and our fellow gardeners.