Native Plants Are, Well, Wild

When you plant a native plant, you might find it spreads aggressively around the yard, crowding out  other plants in the garden. That isn't necessarily a bad thing, but if you are growing natives, you need to be aware that some are pretty wild. 

black-eyed susan, Rudbeckia hirta
along a path; not where I planted the first one

We are urged to grow native plants as a step in preserving them, and to raise the number of insects available for nesting birds to eat, and generally to reconnect local food webs. People who promote growing natives are often wary of growing cultivated or slightly domesticated varieties of the plants, wanting "straight species," meaning that the plants have not been modified or improved by plant breeders.

But many natives will turn out to be "thugs," and you may not want a back yard full of thugs. I took the term thugs from Prairie Up author Benjamin Vogt (link), who in a Facebook post some years ago--that I can't find again--wrote that big bluestem, growing in his yard, was a thug. 

[Definition of thug from Google: "a violent, aggressive person, especially one who is a criminal" and "a violent criminal, bully, or ruffian, often associated with street culture, intimidation, or illicit activities" historically "a member of a group or organization of robbers and assassins in India who waylaid and strangled their victims, usually travelers, and stole their belongings".However the meaning is evolving, for example into "a man who triumphs over systemic and societal obstacles." A dramatic term for aggressive plants but a little much, maybe.]

I wasn't surprised big bluestem was a problem in Vogt's yard. Big bluestem (Andropogon gerardii) was the dominant grass of the tallgrass prairie, the ecosystem now replaced by the Corn Belt. It made up to 80% of that prairie (imagine a bale of prairie hay: 80% big blustem). Vogt lives in Lincoln, Nebraska, in big bluestem's native region. It is really not surprising that a few big bluestem plants in a diverse garden would expand at the expense of other plants toward being 80% of the yard. But of course we want variety in our yards, not a field of big bluestem.

Good condition remnant tallgrass prairie, Lincoln, Nebraska
(Nine-Mile Prairie, September, 1985)
The red-brown is big bluestem.

I have lots of stories of aggressive natives myself:

Many years ago, I planted a native aster, I don't remember which one, into my otherwise ordinary garden. It spread and spread, filling part of the garden, replacing the lawn, until, fed up, I dug it all out. 

I have grown showy milkweed (in Colorado) and common milkweed (in Nebraska) (scientific names listed at bottom); both spread energetically from rhizomes to send up shoots beyond the garden and in the lawn, far from the spot I intended for them. 

Blue circle is at the base of the original showy milkweed;
 red circles are around the base of shoots
 that have come up in the five years since I planted it.

This spring, I invited friends to dig up seedlings of creeping holly grape in my yard because my dozen plants were becoming hundreds and I don't want hundreds of them. My friends were pleased to have the plants and I did warn them.

creeping hollygrape, Berberis repens:
blue is the original plant, red are from its seeds
in the last couple years

The Jerusalem artichokes I grew behind the garage because they were tall and floppy, routinely sent roots under the fence into my neighbor's back yard, working on forming a LARGE patch, not just the few feet I allowed them. 

These are stories of native plants growing in their native region. They were straight species or nearly. And it is probably fair to call them thugs.

But--wild plants have to reproduce themselves. In their native region, the temperatures, rainfall, and soils are ones to which they are well-adapted and they can certainly out-grow Kentucky bluegrass and tea roses. They can scatter seeds and the seeds will likely germinate and survive in the lovely well-watered, fertile conditions of an urban back yard. 

Serviceberry. I planted the row of tall ones. The short one
in the circle is a root sprout, several feet beyond my
intended location. 

Part of what breeders and centuries of cultivation have done is to reduce the ability of garden plants to spread and self-seed. People buying garden plants often want one boxwood or one rose or one peony, not a yard full of them. They want to plant the daphne right there and have it stay there, not, as my serviceberry has done, form a thicket or like the prickly pear cactus spread into a distant flowerbed. [Who knew cactus seeds could travel 50 feet across my yard? I thought all the fruits were still back in the cactus patch and that I needed tortoises, which I don't have, to disperse the seeds. But I do have rabbits and squirrels.]

3-year old cactus seedling (red circle). As a seed,
it somehow moved from the parent plant (blue circle)
to its current location. 

As seen by humans, sterility is a good thing for garden plants. We control how many plants we grow. But natives are not sterile: they had to reproduce for themselves in nature. If we want slower-spreading natives, it will take some years of breeding to produce them. And those will not be straight species.

There's an economic angle to this as well. The demand for native species has shot up in under a decade. Sellers struggle to meet that demand. The plants they can quickly propagate in large numbers are going to be the plants that multiply really well. They will continue do it as garden plants, after they've left the breeders' fields. These fast reproducing plants may not represent all native species very well. It is possible that many native species need special conditions--particular pollinators, particular soil conditions, particular seed dispersers--to reproduce and so are effectively sterile when planted in a garden. But those are not the species available quickly in response to a sudden burst in public interest. 

Consequently, the natives you can readily get right now are pretty aggressive spreaders. It is something people who want to grow natives must to adjust to. Enjoy a meadow-like garden. Or dig up the ones in the wrong spot and give them away.

Having extra plants means I am not very distressed when caterpillars strip the leaves off one or the local rabbit trims another down to a stub. I have enough to share with wildlife.

My natives and my stories of natives are from Nebraska and Colorado (as you will have noticed). The details for New York, Georgia, and Oregon are going to be different, but the principle, that straight species native to your area will likely spread, is universal. Straight species natives are wild and therefore self-reproducing. They will thrive in a yard or garden, and are more, sometimes much more, expansive than the very tame international garden plants we are used to. Don't be surprised and enjoy that vigor. 

 

volunteer
red osier dogwood, Cornus sericea (red stem)

Comments and corrections welcome.

Scientific names for plants mentioned above, because sticking them in got intrusive:

Natives

aster, Symphytotrichium (sunflower family Asteraceae)

big bluestem, Andropogon gerardii (grass family, Poaceae)

common milkweed, Asclepias syriaca (milkweed family, Apocynaceae)

creeping holly grape, Berberis/Mahonia repens (barberry family, Berberaceae)

Jerusalem artichokes, Helianthus tuberosus (sunflower family, Asteraceae)

prickly pear cactus, Oenothera macrorhiza (cactus family, Cactaceae)

red osier dogwood, Cornus sericea (dogwood family, Cornaceae)

serviceberry, Amelanchier alnifolia (rose family, Rosaceae)

showy milkweed, Asclepias speciosa (milkweed family, Apocynaceae)

Exotics

boxwood, Buxus species (boxwood family, Buxaceae)

daphne, Daphne species (daphne family, Thymelaeaceae)

Kentucky bluegrass, Poa praetensis (grass family Poaceae) Native to Eurasia, not Kentucky

peony, Paeonia speccies (peony family, Paeoniaceae)

tea roses, Rosa species (rose family, Rosaceae) 

Terminology Note: 

You can't call natives that you have too many of "invasive" because that term is reserved for exotic [non-native] species. I think we need a word beyond "aggressive" for natives that will take over, to warn gardeners. Thug works, but really isn't something plant-selling websites are likely to use: They aren't going to write on the tag "Note that big bluestem is a thug." "Big bluestem can be aggressive" is better but imperfect. 

References

Weaver, J. E. 1954. North American Prairie. Johnsen Publishing Company, Lincoln Nebraska.

for which species are native:

Ackerfield, J. 2015. Flora of Colorado. 2nd edition. BRIT Press, Fort Worth, Texas. 

Kaul, R. B., J. Sutherland and S. Rolfsmeier. 2011. Flora of Nebraska. University of Nebraska Press, Lincoln, NE.

Kathy Keeler, A Wandering Botanist
More at awanderingbotanist.com
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Please take a look at my books. For those who don't read the internet or prefer books I gathered posts together into actual books, for example

Look Twice, containing stories of plants from western Nebraska and eastern Colorado, available from Amazon  link or from me. This is part of the unique western Nebraska ecosystem that burned with huge wildfires in March 2026.

And

NoCo Notables, Stories of Common Plants of the Colorado Front Range, Many plants have cool stories, about their interactions with other plants and animals and with humans. Go beyond just having a name for the plant, learn more about it. Available from Amazon link or from me.