If you read about gardening and landscaping, even casually, chances are you’ve come across articles or discussions on native plants – especially in recent years. If you’re unfamiliar with why native plants are a recurring subject, I’ll tell you about it and why it’s important.
The Pennsylvania Native Plant Society states that a “native plant is one that occurs naturally in a particular region, ecosystem, or habitat without direct or indirect human intervention.” In other words, a native plant is a plant that functions as it historically has as part of an ecosystem.
The Flowering dogwood (Cornus florida), for example, grows naturally throughout the Southeast, Mid-Atlantic, and most of the Northeast. Because it evolved here and functions as part of our local ecosystems in providing food and shelter for wildlife, it is a native tree. The Kousa dogwood (Cornus kousa) on the other hand, is not native tree to our region and doesn’t benefit wildlife here in the same ways (even though it’s still a lovely tree).
Many plants that don’t grow naturally in Pennsylvania but grow in surrounding states are usually considered native plants too because they still function as part of local ecosystems. One example is purple coneflower (Echinacea purpurea). This iconic native perennial reaches the eastern part of its natural range in Ohio but still serves the same ecological role to pollinators and birds in Pennsylvania gardens as it does in Ohio.
Native plants are necessary for native herbivorous insects, and most are surprisingly picky eaters. The Monarch butterfly is a poster child for this as the caterpillars can only survive on milkweed (Asclepias spp.). As milkweed is removed from the landscape, Monarch butterflies are too. If you’ve seen the news, their population is in freefall. What a tragedy.
These insects, while beautiful on their own, are also important because they are food for everything else. They are critical for bird populations, which depend on insects more than seeds and berries, especially during breeding season. In fact, studies show that 95% of songbirds feed their young exclusively insects. This includes hummingbirds. When insects decline, so do birds. A recent Smithsonian study revealed that bird populations have decreased by 1/3 since the 1970s. The biggest factor is habitat loss with the second being a lack of native plants in suburban lands.
Other animals are also reliant on insects: reptiles, amphibians, and even mammals. Did you know insects make up a substantial part of the red fox’s diet?
While many people may dislike insects, they truth is that they vital for the way the world functions. They provide food for wildlife and pollinate many of our food crops. Without them, many wild plant species would not be pollinated. The world as we know it would not function.
Native plants also produce a multitude of berries, nuts, and seeds at different times of the year providing a diverse array of nutrients. These are especially important for birds in fall and winter as insects die. When these plants are removed and replaced with concrete, lawn, or invasive plants, the diversity of these food sources is lost.
As human activity increases, land for wildlife decreases. When woodlands are cut down, wetlands are drained, and grasslands become housing, wildlife habitat is reduced. As insecticides and herbicides are used carelessly, insect populations and food chains are damaged. When outdoor lights are left on at night, communication between fireflies and moths is disrupted. When invasive plants such as Amur Honeysuckle and Japanese Knotweed invade areas, there is little room left for native plants to grow.
As new businesses and housing go up, habitats for native plants and animals are fragmented or lost entirely. There are lots of examples of this throughout Allegheny and Westmoreland counties.
There are a lot of environmental pressures in the world right now and many require lengthy, complex solutions. Fortunately, there is an easy thing you and I can do at home that will help mitigate the damages mentioned above: planting native plants.
Next time you come in looking for plants – whether it be a few perennials, a tree, or a large landscape overhaul, buy ones that are native. Planting natives is an opportunity for us to give back to the land we live on. For much of the last century, landscaping has often been viewed as a way to dominate the natural world rather than live with it. I think it’s time to challenge the notion.
Contrary to outdated opinions, native plants are not inherently “messy looking.” Nor do you have to have a “wildflower meadow” and give up a tidy landscape. There are many native plants to choose from and professional landscapers have even designed formal European-inspired gardens with plants from eastern North America. Truth be told, you may have some native plants already, as some of our landscape trees like pin oak (Quercus palustris) and sweetgum (Liquidambar styraciflua) are all native to our region.
While I advocate relying heavily on native plants in gardening and landscaping, this doesn’t require a dogmatic approach. Some nonnative plants function and behave nicely in the landscape, including many crabapple trees (Malus spp.) and the perennial workhorse Catmint (Nepeta spp.). The Smithsonian study suggests that to maintain bird levels as they are, Americans should landscape with at least 70% native plants. I think that’s reasonable.
Two of my favorite resources are the Audubon Society and the National Wildlife Federation. Both have tools on their websites where you can enter in your zip code and a list will be generated on what plants grow naturally (or used to) in your area. I particularly appreciate the Audubon’s tool which allows you to search through different plant categories. Their tool also has a “top results” section which lists plants that are easier to find in nurseries and tend to have higher aesthetic value. That said, these lists aren’t comprehensive so don’t end your searching there.
Keep in mind that the reason native plants are important is because they function as part of the ecosystem. They aren’t concerned with manmade state lines. While the shrub Fothergilla (Fothergilla gardenia, F. major) is not specifically native to PA – the peak of its northern range is in North Carolina – it functions in PA as it does in NC because the same insects and birds that utilize it there are the same here. Similarly, willow oak (Quercus phellos) grows wild only in the eastern part of PA but functions the same way here in western PA. The farther the plant grows naturally does mandate more scrutiny but as long as what you plant is native east of the Rockies, you’re most likely in good shape.
We carry many native plants here at Plumline and as our growers have introduced more of them, so have we. We carry many cultivated varieties as well, often coined “nativars.” Nativars have been bred for specific purposes such as dwarf size, diverse flower color, more disease resistance, etc. For example, buttonbush is an awesome wet-tolerant shrub that often grows 10 feet in the wild, but the dwarf form “Sugar Shack” is maintainable at 4-5 feet – much more appealing for the average gardener.
“Nativars” are generally as ecologically productive as the wild grown species. In the above case, buttonbush and its dwarf form are both great plant choices. There are exceptions, however. Double flowering plants (i.e., plants with double the petals of the original plant) tend to have less nectar and pollen so if helping pollinators is your goal, avoid these. Green plants also tend to be more interesting to native insects than red-foliaged plants. If you like red-foliaged plants, use them sparingly.
Here are a few of my favorite native plants.
Possumhaw Viburnum (Viburnum nudum) is a medium sized shrub that is good for a border or as a foundation plant. It hosts wonderful white flowers, glossy green leaves, fantastic red fall color, and beautiful fall fruit. It has excellent durability and deer resistance. We carry the cultivars ‘Winterthur’ and ‘Brandywine’ which are smaller and more compact.
Eastern White Pine (Pinus strobus) is our largest native evergreen. The graceful tree provides nesting sites in spring, seeds for food, and cover in winter. This tree needs room to grow but is a fine landscape choice. We also carry the Weeping White Pine (Pinus strobus ‘Pendula’) which is a great specimen plant.
Woodland phlox (Phlox divaricata) is a species of phlox that thrives in part sun. This species is a groundcover like the more commonly planted creeping phlox (Phlox subulata), another native plant.
Goldenrod (Solidago spp.) is possibly the most underappreciated garden perennial for its durability, long bloom time, and high ecological value. It’s an important pollen and nectar source for pollinators in fall. Deer don’t trouble it and contrary to popular belief, it doesn’t contribute to allergies. There are several native species to our area. I like the cultivar Solidago rugosa ‘Fireworks’, with panicle-shaped blooms that resemble golden fireworks.
Keep in mind that pollinators, such as the Monarch butterfly, require more than flowers to survive. Their caterpillars need host plants. If there are no host plants, there are no butterflies. While many laud butterfly bush (Buddleia x.) as a pollinator magnet, none can lay their eggs on it.
Every year, birds make nests in the nursery stock. This year a female Robin made her nest in one of the evergreens. It was fun to see her perpetually fly away and return to the nest with food for her nestlings every few minutes. Customers enjoyed seeing it too and I appreciated their willingness to select other pines from stock, leaving the nest remain until the babies were old enough to leave. This experience reminds me how important and yet how easy it is to practice good environmental stewardship in our personal lives.
The charisma of birds easily captures our hearts, but reptiles and amphibians need help too. In a previous post, I encouraged people to add a water feature to the garden. A pond or a low basin with nearby low vegetation is a great way to invite these incredible animals to the garden.
In efforts to live with the natural world, I encourage gardeners to reduce their lawn and create more garden beds. Lawns symbolize dominance of the natural world, and the effects show it: lawns are food deserts. They contribute little value and require constant maintenance through mowing (and if you want it to look good, you’ll need fertilizer and broadleaf herbicides). I’ve reduced my lawn to becoming the pathways between garden beds.
Last year, I attended an event for a new local environmental initiative called “ReImagine the Turtle Creek Watershed and Airshed Communities.” This group is a community-led initiative aimed to foster a greener future for southwest PA. It was an inspiring event and the word “re-imagine” has since resonated with me. I think this is a perfect word for how we should approach gardening. Much of the past has favored manicured, “pest-free” plants from other continents, with aims to make the yard almost like an indoor living space. Perhaps we should rethink that.
Let’s re-imagine gardening with natives!
Stay tuned for my next post which will outline native alternatives to many traditional mid-century garden plants, plus more of my favorites.