When planting a naturalistic garden, is having more plants always better? If you ask Kelly Norris, my podcast guest this week and the author of “New Naturalism: Designing and Planting a Resilient, Ecologically Vibrant Home Garden,” the answer is, unequivocally, “yes.” He is an advocate for biodiverse, abundant landscapes that use every square foot to its maximum potential.
Kelly is a modern plantsman and garden communicator with both a bachelor’s degree and a master’s degree in horticulture from Iowa State University. Up until recently, he was the director of horticulture and education at the Greater Des Moines Botanical Garden, where for eight years he directed the nonprofit garden’s design, curation, programming, and facility management. His earlier books include “A Guide to Bearded Irises: Cultivating the Rainbow for Beginners and Enthusiasts” (a winner of the 2013 American Horticultural Society Book Award) and “Plants With Style.”
“New Naturalism,” released this month, is a well-written and beautifully illustrated book on naturalistic garden design and how to achieve a garden that is both aesthetically pleasing and ecologically functional. In it, Kelly shares how to mimic wild spaces in a stylish way that does not require the high maintenance often associated with formal gardens. He explains the basics of botany and what gardeners can learn from nature’s own plant layering and palettes. Through naturalistic design, gardeners can increase biodiversity on the land they steward and support wildlife.
Traditionally, ornamental horticulture has been singularly focused on ornamentation, beauty and aesthetics, Kelly says. Naturalism keeps the aesthetic value of gardening while adding ecological benefits. He calls it an “and and both” scenario, not “either and or.”
A Lifelong Fascination with Plants
Kelly got his start in gardening at a very young age, following his grandmother around her garden asking questions until she put him to work. One of his earliest gardening memories is being tasked with separating four o’clock seeds.
“As curious as I was about plants in grandma’s garden, I was just as curious about wildflowers in roadside ditches and the 40-acre prairie that was just up the road from my grandma’s farm,” he recalls.
Kelly bridged his fascination with plants in gardens and in their native circumstances when he attended college. He says his career has always been about trying to connect the dots to create landscapes in a way that is more aware of and more understanding of plants.
He purchased his half-acre property, known as Three Oaks Garden, in 2017. It’s north of downtown Des Moines on a hillside overlooking the Des Moines River. When he bought it, it had a few foundation plantings, a compacted lawn and “beautiful oak trees around it,” he says, and having grown up under oak trees at his family’s southwest Iowa farm, something just felt right about it. The garden he developed at his new home features prominently in “New Naturalism.”
The Tenants of Naturalistic Garden Design
Naturalistic garden design uses native plants in the areas they are best suited to in order to achieve low-maintenance gardens that will not demand supplemental watering and fertilizing and heavy weeding. Such gardens also provide food and habitat for the insects that are important nutrition sources for birds and other wildlife.
A line from Kelly’s book that really spoke to me is, “Gardens can be both reservoirs of ecological goodness, and beautiful works of art.” To that point, Kelly says naturalistic garden design is not a style, but a strategy. It is based on an understanding of how plants respond to each other and their environment.
Naturalistic gardens are resistant to stresses such as pests, diseases and weeds, and they perpetuate life with a mix of short-lived plants that self-sow and long-lived plants.
This planting model requires a sheer abundance of plants that is different than gardeners have been used to working with. Instead of one of this, three of that and five of those, Kelly designs with seven, nine, 11 or 13 of each plant. That’s because, in nature, plants of the same species are often found in groupings, and there often needs to be many of them for them to perform ecosystem services effectively.
“We have to realize that we are nature, and nature is not separate from us,” Kelly says. “We are a creature in this sort of messy system that we’ve made for ourselves on this planet. And so we can see gardens as existing as essentially a patch in the greater ecological quilt across our landscape.”
Your garden, your neighbor’s garden, the park down the road and the botanic garden are little green stitches that knit together to form the world, Kelly says, and gardeners want to be a functional part of that cohort — for the insects and the birds.
The median lot size in the United States is 0.2 acres, so the reality is most gardens are small, Kelly points out. Be he rejects the notion that naturalistic gardens are only suited to big spaces. Sure, a small naturalistic garden may not help big animals like how National Parks help bison, but they can make a big difference for pollinators, other insects, and invertebrates
Horticultural Layers Inspired by Nature
In an area where plants are dense, like the woods or a prairie, it can be hard to comprehend how vegetation can exist in such great volume and with great diversity. Kelly suggests looking at an ecosystem in layers.
In the woods, it starts from the bottom with the ground plain, or forest floor. The next layer up has smaller trees, bigger shrubs and a thickety texture. Up above is the canopy — the treetops.
Kelly designs gardens the same way nature does, with layers. This achieves a greater density and wastes no space.
He encourages gardeners to look at the square footage they have available for a garden and then ask, how do I plant more than 100 percent of the square footage? At first blush, more than 100 percent doesn’t sound as though it makes any sense, but Kelly says to remember that square footage is in two dimensions, while plants are three dimensional. Looking from the top down and realizing that densely planted plants overlap each other, more than 100 percent of the square footage is accounted for.
Kelly refers to the ground layer as the matrix layer. The structure layer is up top, above our heads, and the part we’re always looking at, in the middle, is called the vignette layer. The vignette is the layer that may be more for us than for nature — but it still contributes to nature when it’s done right.
These denser layers of plants make managing a garden easier and more economical for us as gardeners, as we begin to manage a system rather than individual plants, Kelly says.
A Naturalistic Garden Starts with Living Mulch
Nature abhors a vacuum. If the ground is not occupied by a plant or mulch, something will grow there — and it will probably be a weed.
Kelly designs the matrix layer with living mulch, like sedges, the low-growing grass-like plants in the Carex genus. They’re not showy, but they do a lot of work, he says.
Living mulch will do what other mulches do, and more. It prevents compaction of the soil, holds moisture, suppresses weeds and provides organic matter, among many other benefits.
Understanding Plant Architecture and the Social Life of Plants
Does a plant grow upright and leafy? Does it have a basal rosette or a long, wiry stalk? Whatever the shape and the look, these traits give us clues about how plants function in the world around them, Kelly says. “They’ve evolved over a very, very long period of time in the wild world to adapt and to survive and to perpetuate themselves.”
While most of the focus on plant architecture in “New Naturalism” is on the above-ground part of plants, it also touches on the underground parts — the roots, bulbs, tubers or rhizomes. For instance, Kelly says it’s important for gardeners to understand that a plant with a taproot can’t be divided, while a plant with fibrous roots can be divided easily.
Some plants are colonizers, like running strawberry plants that cover all of the ground. Some are upright and singular, like a cherry tree. Knowing this information about plants will inform and influence the design of a naturalistic garden.
Fertile Soil Is Not Always Best
Figuratively and literally, we’ve just begun to scratch the surface when it comes to understanding soil. One thing we do know is that soils that are dominated by fungi tend to support greater amounts of diversity, Kelly says.
To sustain a diversity of native plants, soil does not have to be fertile. In fact, overly fertile soil can be detrimental to some plants because they are not adapted to such conditions.
Most ecosystems are not very fertile, and they have an inherent component of stress that we can learn from, Kelly says, adding, “It’s that stress that a lot of plants are actually quite adapted to.”
The level of fertility for annual crops is unsustainable for many plants, he points out. The artificial circumstances engineered by gardeners to produce food are not part of the genetic wiring of plants. That means what works for a crop of tomatoes doesn’t work for a perennial garden.
Don’t Clean Up
Gardeners have long been taught to put the garden to bed at the end of the growing season by cleaning up — but why?
“What is dirty?” Kelly asks. “What needs to be cleaned up out there?”
The seeds in spent flower heads are food for birds all winter, and beneficial insects, including pollinators, overwinter in hollow stems and plant debris, such as fallen leaves.
Because Kelly leaves plants standing all year, even in the middle of February, despite his prairie being under snowpack for months, he can see sparrows and dark-eyed juncos out his window. They feast on the seedheads that many gardeners are accustomed to removing.
Weed Smarter, Not Harder
The presence of weeds can have less to do with the weeds themselves and a lot more to do with something happening in the system that’s encouraging weeds to grow. Plus, pulling out every single weed can actually create circumstances that will allow even more weeds to thrive. It disturbs more seeds, stimulating seeds in the soil to germinate.
Dandelions are one of those weeds that love disturbed ground, and Kelly says he’s tempted to write a book all about them. They are one of those plants that, the more we learn about them, the more of a mystery they become. Where they originate from is unclear, though we do know that they follow humans and are found on every continent. Their presence has more to do with what we do to the earth than what we refrain from doing.
White clover is another generalist that can survive in many circumstances, Kelly says. It is often thought that the presence of white clover has to do with a nitrogen issue in the soil, but, he says, it’s actually a sign of a phosphorus issue because other plants couldn’t grow in the same spot.
Pulling a weed is a quick fix but not the more efficient way to tackle a weed problem. Kelly’s approach is to question why a weed is thriving in a certain area and to address the underlying reasons.
A Palette for Successful Planting
Kelly’s book originally started out with the idea that it would be an ecological planting recipe book. But he soon realized that in a world as large as ours, it could never be as simple as picking one recipe out of a list of many. Planting and gardening are very local, and there are nuances that are hard to convey.
Instead, he addressed naturalistic landscaping with agnosticism toward where the reader is located. The book is about every home and every front yard, and how to approach it with an ecological view. Giving gardeners that knowledge also gives them the tools they need, which is more useful and practical than a list of plants that may not be applicable to their region.
Climate Change Changes the Rules of Naturalistic Garden Design
While we know that it’s important to build gardens from native foundations, Kelly says, we also know that because of climate change, the rules are changing to the game even as we’re playing it.
He notes that where he lives, in Iowa, winter temperatures have reached new lows in recent years. At the other end of the extremes, in warm regions, stretches of temperatures over 100 degrees have gotten longer.
Identifying which USDA hardiness zone we live in is supposed to tell us what plants will overwinter in our region, but that information becomes less reliable as seasonal weather becomes less predictable.
Kelly’s advice is to just keep planting, thoughtfully and intentionally. Your garden may be your art, but it’s art that is alive and part of the world.
“It’s the element of time and change in gardening that I find so enriching, personally, but also so fascinating and educational about the world,” he says. “Gardening is far closer to choreography than it ever has been to painting, right? It’s not a static picture on the wall. It’s happening in front of us in time and it’s slow. Humans don’t like slow — we don’t, it doesn’t work with our brains. It’s so hard for us to imagine that something like our garden can be quite different five years, 10 years from now.”
If you haven’t already listened to my conversation with Kelly Norris on naturalistic garden design, you can do so now by scrolling to the top of the page and clicking the Play icon in the green bar under the page title.
Have you integrated naturalistic garden design into your landscape? Let us know in the comments below.
Links & Resources
Some product links in this guide are affiliate links. See full disclosure below.
joegardener Online Gardening Academy™: Three popular courses on gardening fundamentals; managing pests, diseases & weeds; and seed starting.
joegardener Online Gardening Academy Master Seed Starting: Everything you need to know to start your own plants from seed — indoors and out.
“Plants With Style” by Kelly Norris
Disclosure: Some product links in this guide are affiliate links, which means we would get a commission if you purchase. However, none of the prices of these resources have been increased to compensate us. None of the items included in this list have any bearing on any compensation being an influencing factor on their inclusion here. The selection of all items featured in this post and podcast were based solely on merit and in no way influenced by any affiliate or financial incentive, or contractual relationship. At the time of this writing, Joe Lamp’l has professional relationships with the following companies who may have products included in this post and podcast: Rain Bird, Corona Tools, Milorganite, Soil3, Exmark, Greenhouse Megastore, High Mowing Organic Seeds, and Wild Alaskan Seafood Box. These companies are either Brand Partners of joegardener.com and/or advertise on our website. However, we receive no additional compensation from the sales or promotion of their product through this guide. The inclusion of any products mentioned within this post is entirely independent and exclusive of any relationship.