Most of us already know that native plants evolved to live here: that's why they're native plants. And many of us also already know that this gives them a leg up, where evolutionary adaptations to our area are concerned. Dry summer? No worries: you should have been here in 1929. Cold winter? You don't know what cold is: you should have seen January 5 in River Vale back in 1904. Native plants survived all of that. And that's not even getting into the times before we were keeping historical records: many native plants' relationship with the area stretches back to when mastodons still could help distribute their seeds! Over their long, long, (long) history with the region, native plants have weathered the highs and the lows, the floods and the droughts, and the species that survived have adapted to handle anything that the region is likely to throw at them.

But, of course, nuance once again raises its pesky head: "adapted to anything the region is likely to throw at them" doesn't cover quite all of the modern age's challenges. It's a surprisingly common misconception that native plants are a bit like Jack's magic beans, from the fairytale with the beanstalk. Surely, if I simply plant native plant seeds, nature will right itself, right? Invasive knotweed and mugwort will vanish, and suddenly I will have an edible food garden simply dangling from the trees for the taking? Right?

It's a beautiful fantasy, but unfortunately, it's about as realistic as Jack's beanstalk. Nature will not simply "right itself" with the application of a sprinkling of seeds. Why not? Well, invasive species are generally so successful because they've been removed from their native environment where they (like our native plants) evolved to handle the challenges of their region. Once removed from that environment, they no longer face their natural challenges, they're isolated from their natural biological controls like herbivores and insects, and suddenly those adaptations (which make sense where they're from!) run wild. And they're not alone in this: our native species can be invasive elsewhere in the world, too! And as much good as our native plants do for us here, when they escape and become invasive elsewhere, they're just as harmful there as invasive plants are here. Evolutionary adaptations to a specific region are an advantage, but so is being removed from that region and getting sent over the rainbow to a different continent, where troubles melt like lemon drops and the local herbivores don't know your leaves are edible (especially advantageous here in the northeast where we have problems with deer overpopulation).

Why, then, is it important to plant native species? And what does this have to do with climate resilience??

Hello Ecology My Old Friend

To put it at its absolute simplest: it's important to plant native species because bugs eat plants. We all remember the food chain from sixth grade science, right? Plants (aka producers) produce energy from sunlight, bugs/herbivores/seed-eating birds eat those plants, and then carnivores (other birds, amphibians, reptiles, larger bugs, foxes, and so on) eat the bugs and herbivores. Et cetera.

Imagine, then, what happens when invasive plants crowd out the native species, leaving the bugs and other herbivores of a region with a lush forest of exclusively invasive plants to choose from, none of which they recognize (and/or can use) as food. What happens when the Monarchs lay their eggs on invasive swallow-worts (Vincetoxicum spp.), that 'smell' like a Milkweed but will kill any monarch caterpillars that try to feed on it? Or when the invasive plant species start to smother the native plant species, leaving, say, all of the Monarchs in the region with just a few beleaguered Milkweed plants to lay all of their eggs on? What happens when the Monarch caterpillars eat all the foliage off of those few remaining plants? What happens to both the Monarchs and the Milkweeds when those plants die because they have no leaves left? Insects are a little bit hard-wired, and a lot of them have very specific biological needs and adaptations. It's not a matter of choice, necessarily: they may need to eat one specific type of plant. So what happens when none of the plants (producers) in an ecosystem are usable by the first level of the food chain? That food chain starts breaking down at a very basic level. With no native plants for the native bugs to eat, there are no native bugs. And with no native bugs, there are no native salamanders, or frogs, or birds.

Remember 'Silent Spring'?

Obviously it's more complicated than that. Pollinators exist and are important (although many of them also require specific native plants at some point in their life cycle) and there are plenty of carnivorous species of insect that wouldn't have the first clue what to do with a native plant leaf, regardless of how you cooked it. And yes, technically speaking those "bugs" we've been talking about are more accurately "insects" (bugs are a specific subtype of insect, and not all of them eat plants), but the point remains the same. Many native insects eat plants. Even a lot of those pretty pollinators we all plant flowers for (butterflies anyone?) start as caterpillars, and caterpillars? Well, they eat leaves. And often, those caterpillars are specialists that can only eat the leaves of really specific plant species. Spicebush Swallowtail caterpillars (Papilio troilus) only eat Spicebush (Lindera spp.) and Sassafras (Sassafrass albidum) leaves. The caterpillars of most species of Fritillary Butterfly only eat violet leaves. And as we all know, Monarch (Danaus plexippus) caterpillars only eat Milkweed (Asclepias spp.) leaves. And that's just the tip of the veritable iceberg when it comes to insect/host plant specialization.

Io Moth (aka Peacock Moth) Caterpillars (Automeris io), on a Pussy Willow (Salix discolor). These are stinging caterpillars. In fact, these ones stung me, specifically, when I brushed past them in shorts, and was rapidly filled with both regret and urticating hairs. They're also native, and beautiful, and fascinating, and it was easy enough to move them slightly further from the path. Look up what the adult moths look like some time; despite the stings, it was a delight to see them!

Hamlet wasn't talking about caterpillars, or even insects in general, when he said "There are more things in Heaven and Earth, Horatio, than are dreamt of in your philosophy," but it would have been fair if he had been: our understanding of the natural world all around us is incomplete. We simply don't know every little insect, where it's found, what it eats, and what role it plays in our natural world. New discoveries are made every day, and not just halfway across the world: to imagine we have the necessary knowledge to fix all of this if we broke it betrays an overly simplistic worldview. Much of the funding that goes into entomological grants is focused on crop protection, which means we know less about your average (pardon the pun) garden-variety bug than you might think. We ourselves have found caterpillars on our farm that we couldn't match to an ID on the host plant we found them on, and there are plenty of insect species out there where their host plant simply remains unknown. Just last week we found a jumping spider on our farm that's only had 344 global sightings on iNaturalist. It was about the size of a poppy seed, and despite doing this for almost thirty years, we'd never seen one before. There are more obscure things out there than most people appreciate, right in our own backyards and gardens. The point being, not only do we not know every little thing about the natural world, we aren't even entirely certain of what we don't know. Perhaps we've ID'ed the insect/creature, but do we know everything about its life cycle? Do we know where and how it overwinters? What it eats? Who eats it? What critical place it holds in the overall environment where it is found?

What we do know is that the ecology of our landscape is based, at the very first level of the food chain, on native plants, which evolved in tandem with all the tiny insects and soil microbes and creatures that we don't know much about. We can't fix it if we break it, but we can help to keep it from breaking in the first place.

Every year, American Lady Butterflies (Vanessa virginiensis) absolutely mob the Pussytoes (Antennaria sp.) we grow for sale, because they're one of the very few things the caterpillars of this species can eat. So if you see us "selling out" of Pussytoes every year starting around late June, now you know why. It's not that we don't have them, they're just busy being native caterpillar food.

How To Keep From Breaking It

Our native landscape is full of biodiversity, and our best bet for maintaining the richness of our natural world is to support that biodiversity. A wider variety of native plant species will support a wider selection of insects, including generalists (insects that can eat a variety of species), and all manner of specialist species (including unobtrusive, little-studied specialists) that can only eat one plant species. If a caterpillar shows up and starts eating your native plants, that shouldn't be a source of panic, but rather a sign that your plants are doing their job!

Likewise, the best way to create climate resilience in your garden is to plant a wide variety of species that are adapted to your environment. If your yard is a loamy woodland, don't plant species that need well-drained soil in a sunny location. The fact of the matter is, there may be times when our current trajectory of extreme weather does kill some of your native plants. Just because they've adapted to the extremes of our region, doesn't make them immune to being washed away by a flood, and just because the species itself has survived thousands of years in the region, doesn't mean that individual plants can't be killed by harsh conditions, especially as conditions change and become more extreme as climate change impacts local weather. So the best plant for your yard is the one that will successfully grow in the conditions you have, with as little intervention on your part as possible (aside from keeping invasive plants from crowding it out). The best keystone species in the world won't do your local insects any good if it doesn't survive or thrive in the conditions of your garden, and just because a native plant doesn't say it's a host plant online, doesn't mean that species isn't important to some insect, bird, or other creature: don't forget, we don't know everything. It's more important to focus on planting a variety of species that will actually grow for you than it is to seek out the 'best' species while ignoring its preferred growing conditions, watch it die because you didn't make sure it was suited to your garden, and give up in frustration. We can't optimize the food chain, and there's no 'one easy trick' to any of this: supporting our environment means maintaining as broad a base as possible to support as much of our natural world as we can.

There are lots and lots (...and lots) of native plants to choose from. Odds are, you'll be able to find a large number of species to match your conditions!

And Finally: How To

So how, then, beyond all the philosophizing, do you make a garden with native plants that's resilient against climate change and extreme weather conditions?

First, once you've identified the conditions of your garden (is it sunny? dry? rocky? clay?), absolutely focus on planting a variety of species that are suited to those conditions. Keystone species are incredible, and identifying them has been a huge step forward in helping support native insects and birds, but that's far from the end of the story. If all your (proverbial) eggs are in one basket, it will really set you back if something happens and that species doesn't survive in your garden. Yes, by all means, plant a White Oak (Quercus alba) if you can! But then find yourself a few different spring-blooming plants, a few summer-blooming plants, a few fall-blooming plants, a few sedges and native grasses, and maybe a few smaller shrubs or trees that act as host plants for various butterflies and other creatures. Remember, the idea is variety. Don't just plant one fall-blooming aster and call it a day, because not only does variety give you an opportunity to try different things to see if they work in your garden, it also broadens the scope of the number and type of insects you're supporting.

Second, if and when a drought hits, if you have water to spare (if there haven't been water restrictions placed on your area), focus your energy on watering your trees. That white oak you planted? Work on saving that. Don't worry about setting up a sprinkler in your garden, now is the time to focus on saving your trees. Yes, your garden may suffer, and some of your plants, even your native plants, may die. But in a drought, there's only so much water to go around, and trees are vital. They provide the most biomass and subsequently the most habitat. They're an ecosystem all on their own. They cool the surrounding landscape, helping to mitigate the effects of a warming planet and the drought itself, and one bad year can impact the health of a tree later down the line--if it doesn't simply kill the tree outright. If you have to replant your asters, or grow them from seed again, it will take you maybe two years (and they may have seeded in themselves! Give it a year and you may see sprouts coming back up all on their own). But a tree? A tree is a long-term commitment. When severe droughts hit, prioritize your trees and shrubs.

Third, look into erosion control. Truly spectacular rain events are occurring with about the same frequency as droughts these days. We've talked before about the over-use of mulch, but now more than ever it's a good idea to make sure you're using native groundcovers (which hold onto dirt far better than mulch). It's also important to allow your plants to grow next to each other rather than keeping them several feet apart like scandalized attendees at a regency-era ball. If your plants are growing more closely together, their roots will intertwine and help to hold the dirt in place in the event of a gully-washer. Their leaves will also break up the rain drops before they hit the soil, also lessening erosion. If, however, there are large gaps between your garden plants, the likelihood of your dirt washing dramatically away rises significantly. This is especially true if you live on or near a slope.

Fourth, don't forget about sustainability! Another reason to plant groundcovers rather than using mulch is because mulch is far less sustainable. If you're going to use mulch, we recommend contacting an arborist for wood chips rather than buying dyed mulch at a box store. Sustainability is its own reason to plant native species, especially ones suited to your garden: they require far, far less maintenance than many types of traditional non-native garden plants. No need to set up a soaker hose in your garden if you plant species that are perfectly happy living in dry soil!

Fifth, bear in mind that the climate is, broadly speaking, getting warmer. Between 1990 and now, our USDA Hardiness Zone rating on the farm has gone from 6a, to 6b, to now 7a, meaning our annual average minimum temperature has gone up 10 degrees. This doesn't rule out the possibility of aberrant very cold winters due to strange climate-based wintertime weather patterns, but it's worth keeping in mind when choosing species to put in your garden. If a species is native mostly north of you, and its range only just reaches down to where you are, it may find your increasingly warm summers and oddly balmy winters just too hot to handle. Species where the bulk of their range is south of you may be better suited to handling your area's developing new normal, and it will help support the wildlife species whose ranges are slowly shifting northward, as well.

Sixth, remember: one of the reasons native plants are important is because, as we've talked about, things eat them. Our Milkweeds don't look their best when they're being chewed on by Monarch caterpillars, milkweed beetles (did you know they purr?), and milkweed tussock moths, but these plants are busy doing a very important job: they're chugging away at the bottom of the food chain, acting as a food source for those insects. That means you need to get used to seeing bugs on your plants, and not just on Milkweeds! We've had a surprising number of people contact us after planting host plants (especially, but not exclusively Milkweeds), alarmed because there were caterpillars eating their plants, which is slightly like bringing a pie to a potluck and getting upset that people are eating slices of it. Relax! Your plants are doing exactly what they're supposed to.

Seventh, like we talked about above, you will likely have to do at least a little garden maintenance to protect your native plants from being crowded out by invasive species. But such is the life of a gardener!

It takes a village (of native plants) to raise a butterfly: Eastern Tiger Swallowtail butterflies (Papilio glaucus) as caterpillars feed on Wild Black Cherries (Prunus serotina), Tulip Poplars (Liriodendron tulipifera), or Sweetbay Magnolias (Magnolia virginiana), but once they emerge as adults, they need flower nectar, and particularly seem to enjoy Joe Pye Weeds like this Hollow Joe Pye Weed (Eutrochium fistulosum).

Not Death By A Thousand Cuts, But Life By A Thousand Gardens

Climate change is complicated, and extreme weather is difficult to plan for or work around. The environment is already complicated; adding in climate change makes it that much more complicated. But it's worth working to help sustain our natural environment, and the fact of the matter is, a scattered series of native plant gardens is a vital resource to our environment when it's getting harder and harder for our native plants (and the creatures that rely upon them) to sustain themselves, faced with invasive species, habitat disturbance by people, and culturally aggressive landscaping practices. In the past, when faced with extreme conditions like long droughts or hard winters, these species survived by having small holdout populations situated in ideal locations: maybe next to a natural seep helping them survive a drought, or in a sheltered location helping them survive extreme cold, from which they would then repopulate an area. Our gardens can be that, giving these plants a sanctuary in which they can survive, and from which they can spread their seeds. And a sanctuary for plants is a sanctuary for everything that relies on those plants, from insects right up along the food chain, helping to sustain a multitude of at-risk species. The more of us that do it, the better off the environment will be. This work, along with the education to understand why it's important, is a baton we pass from person to person. It's not all on any one of us, but it's the responsibility of all of us. Out natural world is important! It's worth the effort to save.

It's not all gloom, doom, and hard work, either. Lest we forget, the natural world is beautiful, and majestic, and a privilege to see...

It's also, often, delightfully silly and endearing.