In GardenRant’s 18-year history we’ve tackled more than a few controversial topics, including Marianne’s recent post about advocates of pure nativism, to which Ranter emeritus Thomas Christopher then responded. Lively discussions ensued! I love seeing disagreements aired and explored honestly and based in facts. And with an open mind!
In that vein, a recent episode of Thomas’s excellent podcast Growing Greener explored “Blending Natives and Non-Native Plants” through an interview with Karen Bussolini. She’s a garden writer, photographer, speaker and coach who also works as horticultural advisor to White Flower Farm. (We first hear about the company’s sustainable practices, which are indeed impressive.)
Getting to the subject of growing both native and nonnative plants, Karen’s stance is that “It’s a large house and there’s room for everyone,” while citing the study showing greater biodiversity in the Great Dixter garden than in the surrounding countryside.
How to Support MORE Pollinators by Including Nonnative Plants
Quoting Karen: “When it comes to pollinators you want mass and connectivity, so you want a lot of flowers. And the kind of rule of thumb is you need to have at least three plants blooming together from the earliest in the season to the very latest.”
Daffodils at River Farm, AHS headquarters in Virginia.
“Abundance and diversity of flowers leads to abundance and diversity of insect life, and I’ve come to think of the purpose of gardening is supporting insects. They’re so important! So those early bulbs – when the earliest bees come out of the ground there’s not a lot of food. So crocuses and snowdrops and early bulbs like that, daffodils – the earliest ones, it’s probably only the honeybees that come out on a warm day but pollinators are like the canaries in the coalmine. They tell you about the whole habitat, the whole ecosystem. And I have certainly seen a lot of bumblebees in my daffodils. So there’s food there.
Hummingbird on salvia in my garden.
“A lot of annuals – we have some highly bred ones that don’t really feed anyone but we have some annuals that are just absolutely buzzing with native pollinators and hummingbirds and butterflies. So plants like verbena bonariensis nasturtiums, ageratums, and there are a lot of annuals that are – some of them are tender perennials that are native to Central and South America or the far Southwest, but our bees don’t know that! They absolutely flock to the salvias, zinnias, tithonia. Sunflowers are not native here – they’re native to the Midwest – but they’re one of the absolute best. Dahlias, the big fluffy ones that are double – no. But you plant a few single dahlias and you’re going to see a whole lot of native bees feeding from them. Agastache, some of the Southwestern native ones, are just absolute bee magnets and the hummingbirds love them, too.
“You mention hostas. Boy oh boy there are some great hostas that have really attractive flowers – not the old-fashioned ones – that are absolutely full of bees and hummingbirds.
Alliums in my garden.
“Early in the season, hellebores. I would not be without alliums, both the bulbs and the perennial alliums, especially the bulbs – they are absolute bee magnets. And a lot of perennials that have umbel shaped flowers, the tiny flowers feed lots of tiny insects.
“Patrinia. We have dauchus dara, (also known as the flowering carrot, wild carrot, or Queen Anne’s lace), which has maroon flowers and pink flowers and white flowers.
Nepeta in one of my adopted gardens.
“How can you be without nepetas or calaminthas? I know that my yard at home is full of ajuga, and those blue flowers just absolutely come with bees.
“Early morning – bumblebees can fly earlier and farther than any other kind of bees and sedum ‘Autumn Joy’ and Japanese anemones were completely covered.
“Then they’re not out yet but in the late fall a lot of native plants – the asters and the goldenrods are so important, they’re really critical food sources for bees and butterflies, but what are those things supposed to eat when those things have passed? We have extended falls, so the native plants have gone by and the bees are still active and that’s when they’re going to really flock to the anemones but also to monkshood.
What about feeding caterpillars?
Black swallowtail caterpillar on bronze fennel in my garden.
Tom mentions special functions that native plants can perform, like being larval hosts for caterpillars, many of which are adapted only to specific native plants. He continues: “So I think it’s important to include both, but you make a very persuasive case that you can be feeding and benefiting a lot of wildlife by including nonnative plants in your garden.”
About feeding caterpillars, Karen says, “I’m glad you mention larval food plants because there are such tightly integrated relationships with native plants. But the next kind of class of plants that I would not be without are in the vegetable gardens and in the flower gardens – herbs. I love fennel and bronze fennel and dill and it’s a little bit hard to harvest them sometimes because the swallowtail butterflies use that whole family as a larval food plant. To my surprise, the daucus dara, which is a Welsh carrot, I had some growing… and saw black swallowtail caterpillars. So plants like mint and oregano and basil and other herbs are important for pollinators – I don’t think they’re larval food plants but certainly fennel and dill are.”
And I love this – Karen recommends that we “just be observant, spend time in the garden looking. What plants are buzzing with pollinators?” And her advice to listeners who want to be environmentally responsible but still enjoy traditional garden favorites? “Go for it. You have to enjoy it. Educate yourself.”
On the growing dominance of strict nativism
Referring to the strict nativism that Marianne and others are complaining about, Tom says “Whatever native plant purists may say, the leaders of the movement do NOT say you should only grow native plants. Douglas Tallamy has never said that you should exclude introduced beloved nonnative plants from your garden. Larry Weaner, who I’ve worked with, includes both in his garden because he wants to keep his clients, as well as the wildlife happy.”
That’s true, though I wish Tallamy in particular would encourage inclusion of nonnatives for the benefits outlined above. But there are plenty of people and organizations who do promote the use of native plants ONLY, including: writers Benjamin Vogt, Ginny Stibolt and Jenny Reed, and these organizations: Xerces Society, National Wildlife Federation, Pollinator Partnership, Wild Ones, Chesapeake Bay Foundation, U.S. Fish and Wildlife Service, Alliance for the Chesapeake Bay, Penn State Extension, Ohio State, Cornell Extension, Michigan State, (which repeats debunked claims about natives having deeper roots), the USDA and even Architectural Digest Magazine.
(I found just a few organizations that include nonnatives in lists of plants for pollinators or rain gardens – Oregon State, U. New Hampshire and the Cincinnati Zoo and Botanic Garden. And many gardening publications.)
Then there are the untold numbers of government and nonprofit grants that forbid the use of nonnatives in projects they fund. And the agencies targeting plants like the eucalyptus trees in California for removal because they’re not native there.
My apologies to anyone I misidentified as recommending or requiring only natives. I’m happy to correct this post if asked.
It’s not just “traditionalists”
Thomas mentions the many gardeners who are “reluctant to give up introduced garden plants, the old favorites that didn’t originate many of them in North America but are really hard not to love. You know, bearded irises, hybrid roses, hostas, et cetera, things that have been favorites since most gardeners’ childhoods. And at times this has become a point of conflict. I’ve been told by resentful traditionalists that they’re tired of being told that they are irresponsible for growing anything other than natives.”
Well, I’m one of those gardeners growing both natives and nonnatives but not because I’m keeping “traditional” garden plants like those listed, which I grew tired of long ago. In the last 15 years or so I’ve ditched the lawn (in two gardens) and filled the spaces with plants from around the world that attract pollinators and provide other ecological services, as well as beauty for me and for passersby.
So what to call gardeners like me? How about inclusive eco-friendly gardeners? Yeah, that fits.