Pennsylvania native plants, and the invasives to kick out

Native plants and local wildlife evolved together here for thousands of years — long before anyone argued about whether it's a hoagie or a sub. There may be debate around native cultivars. But I think Pennsylvanians can at least agree it's absolutely not a grinder.

What's not up for debate is that your neighborhood bugs, birds and critters depend on native Pennsylvania plants for food and shelter. These plants are vital hosts that help them survive and make more bugs, birds and critters.

As a gardener, one of the most important things you can do to help local wildlife is to grow the native plants in your garden that support them.

But not every plant helps. There are some aggressive invasives (even some sold at garden centers) that can do serious ecological damage.

The difference between the two is knowing which plant you're looking at, and whether it belongs here in Pennsylvania.

Truth is, a plant that feeds monarchs in Pittsburgh can overrun meadows in Hungary. A native in one place is a transplant in another. And some transplants can turn into serious ecological bullies.

Which means the question of "is this a good plant?" always depends on a second question: good where?

For Pennsylvania gardeners, here's the starting point: the native plants worth planting on purpose, and the aggressive spreaders worth kicking out.

Some of the best native plants for Pennsylvania gardens include butterfly weed, wild bergamot, cardinal flower, golden alexanders, flowering dogwood, white oak, spicebush and serviceberry. Pennsylvania also regulates invasive plants gardeners should avoid spreading, including Japanese knotweed, mile-a-minute, Callery pear, Japanese barberry and multiflora rose. What counts as native or invasive is regional, so the right answer depends on where you garden.

How this list was checked: Pennsylvania nativity was checked against the Flora of Pennsylvania and DCNR sources, with Kew's World Checklist of Vascular Plants used as an additional range/taxonomy source. Pennsylvania invasive status comes from the Department of Agriculture's current Controlled Plant and Noxious Weed lists. Plant status can change as taxonomy and regulations are updated, so this page is periodically rechecked.

New to this? Start with what "native" actually means — the same plant can belong in one place and cause harm in another.

Pennsylvania natives worth planting

These are just some of the plants that have evolved alongside Pennsylvania's bees, butterflies, and birds. When you plant them in your garden, you're helping out an entire ecosystem.

For pollinators and color

• Butterfly weed (Asclepias tuberosa) and common milkweed (Asclepias syriaca) — Monarch caterpillars can only eat milkweeds, so planting locally native milkweed species means planting habitat for monarchs. If you're growing these in your garden, you're growing butterflies. Full sun · butterfly weed: dry, lean soil, 1–2½ ft · common milkweed: average soil, spreads by rhizome, 3–5 ft · bloom early–mid summer
• Wild bergamot / bee balm (Monarda fistulosa) — a pollinator magnet with lavender blooms. This one will make your garden a popular one with the beneficials. Full sun to part shade · dry to medium soil · 2–4 ft · blooms mid-summer
• Black-eyed Susan (Rudbeckia hirta) brings a pop of sunshine to your garden in mid-summer. Pollinators love it. Full sun · dry to medium soil · 1–3 ft · bloom early summer into fall
• New England aster (Symphyotrichum novae-angliae) and Canada goldenrod (Solidago canadensis) — these two are important late-season food sources for pollinators. When most other flowers are tapped out for the season, these two help your Very Hungry pollinators make it through the autumn. Full sun · medium to moist soil · 3–6 ft · bloom late summer into fall · Canada goldenrod spreads readily
• Dense blazing star (Liatris spicata) — Blazing star adds shape to your garden with striking vertical purple spikes in mid-to-late summer. They're a magnet for monarchs and other butterflies. Goldfinches love the seedheads after they're done flowering. Full sun · medium, well-drained soil · 2–4 ft · blooms mid-to-late summer
• Cardinal flower (Lobelia cardinalis) — hummingbirds go gonzo for the electric-scarlet spikes in late summer. Keep it in a damp spot or a rain garden, sit back and enjoy the show. Full sun to part shade · moist to wet soil · 2–4 ft · blooms late summer
• Wild columbine (Aquilegia canadensis) — Another hummingbird favorite, these nodding red-and-yellow bells come out in spring, just in time to welcome the ruby-throated hummingbirds back into town. They're happy in part shade and rocky spots. Part shade · dry to medium, well-drained soil · 1–2 ft · blooms spring
• Sweet Joe-Pye weed (Eutrochium purpureum) — Joe-Pye weed is a back-of-the-border giant, topped with dusky-mauve flowerheads that butterflies swarm in late summer. Full sun to part shade · medium to moist soil · 4–7 ft · blooms mid-to-late summer
• Woodland phlox (Phlox divaricata) — Woodland phlox is an important snack in early spring for butterflies and long-tongued bees looking for nectar. It's a good choice for shady areas and forms low, fragrant drifts of lavender-blue flowers. Part to full shade · medium, humusy soil · ~1 ft · blooms spring
• Golden alexanders (Zizia aurea) — Golden alexanders form flat gold umbels in late spring that bees and other pollinators love to comb through. It's an early nectar source and the host plant for black swallowtail caterpillars. Full sun to part shade · medium to moist soil · 1–2½ ft · blooms late spring

Trees and shrubs

Small trees & understory

• Flowering dogwood (Cornus florida) and eastern redbud (Cercis canadensis) — these showy understory bloomers light up a Pennsylvania spring. Part shade to full sun · medium, well-drained soil · 15–30 ft · bloom spring
• Serviceberry (Amelanchier arborea) — This is one of the best small trees you can grow in a garden: white spring flowers, fiery fall colors and berries in June that the birds can't get enough of. Full sun to part shade · medium, well-drained soil · 15–25 ft · blooms early spring
• Witch hazel (Hamamelis virginiana) — this one blooms when everything else is winding down, with spidery yellow flowers in late fall, just as the leaves are coming down. Part shade to full sun · medium to moist soil · 15–20 ft · blooms late fall

Shade & canopy trees

• White oak (Quercus alba) — if you have room for one major wildlife tree, native oaks are hard to beat for how much wildlife they support. Full sun · medium, well-drained soil · 50–80 ft · long-lived shade tree
• Tuliptree (Liriodendron tulipifera) — a fast, towering native with tulip-shaped blooms high in the canopy that keeps pollinators busy in spring. Full sun · medium to moist, deep soil · 70–90 ft · blooms late spring
• Black gum (Nyssa sylvatica) — Black gum earns its space three times over: spring flowers for insects, fruit for birds and some of the most electric red foliage of a Pennsylvania autumn. Full sun to part shade · medium to wet soil · 30–50 ft · standout fall color
• American basswood (Tilia americana) — When bees spot this shade tree in bloom they make a bee-line (Sorry. Couldn't resist.). In full bloom it practically hums with happy bees. Full sun to part shade · medium to moist soil · 50–80 ft · blooms early summer

Shrubs

• Spicebush (Lindera benzoin) — This aromatic understory shrub is the host for spicebush swallowtails. Thrushes love snagging the red berries it puts out in fall. Part shade · medium to moist soil · 6–12 ft · blooms early spring
• Buttonbush (Cephalanthus occidentalis) — Buttonbush makes pincushion globes of white flowers that pollinators mob like a crowd on Black Friday. It's happy in the wet spots nothing else wants. Full sun to part shade · moist to wet soil (takes standing water) · 6–12 ft · blooms summer
• Black chokeberry (Aronia melanocarpa) — Pollinators love black chokeberry for the white spring flowers. Birds love it for the dark berries that help get them through winter. You'll love it for the brilliant red, orange and purple show it puts on in the fall. Full sun to part shade · medium to wet soil · 3–6 ft · blooms spring

Native gardening across Pennsylvania

Pennsylvania has some diverse growing conditions. The southeastern Piedmont around Philadelphia stays milder longer, the Allegheny ridges are cold and rocky through the middle of the state, the northern tier gets long snowy winters, and the Lake Erie region has its own lake-effect climate. A plant can be native to Pennsylvania and still be a poor fit for the particular sun, moisture, soil, and elevation in your yard.

So use the list above as a starting point, not a shopping list. The best native plant is one that both belongs in your region and actually likes the conditions you can give it.

Invasive plants Pennsylvania gardeners should avoid

Invasive plants can spread aggressively into natural areas, displace native vegetation and change the food and habitat available to wildlife. In Pennsylvania, some are serious enough that the state regulates them as noxious weeds. TLDR: these plants are bad news.

Here are the usual suspects:

Pennsylvania-listed noxious weeds

Pennsylvania regulates these under the Controlled Plant and Noxious Weed Act. Plants designated as noxious weeds generally cannot be sold, transported, planted or otherwise propagated in the state, although Pennsylvania allows specific approved exempt cultivars of a few listed species. Giant hogweed and kudzu are Class A weeds targeted for eradication; widespread plants including Japanese knotweed, multiflora rose and Callery pear are Class B weeds.

• Giant hogweed (Heracleum mantegazzianum) — true to its name, this one is big: it can grow more than 10 feet tall with leaves up to 5 feet wide. ID it, but NEVER touch it. Its sap can cause burns, blisters and scarring.
• Japanese knotweed (Reynoutria japonica) — Japanese knotweed is one of the worst. It spreads aggressively by underground rhizomes, can exploit cracks and disturbed ground, and is notoriously hard to get rid of. If it's growing in your yard, this is one you'll want to contact the Penn State Extension office about to learn how to deal with it.
• Mile-a-minute (Persicaria perfoliata) — a fast annual vine with backward-pointing barbs and little blue berries. It earns the name: it can put on a few inches a day and blanket a whole hedgerow in a single summer.
• Multiflora rose (Rosa multiflora) — with clusters of white flowers, this one is a serious menace. It can regrow from seeds or stems and, like the other invasives on the list, chokes out native plants wherever it goes.
• Bush honeysuckles (Lonicera maackii, L. morrowii, L. tatarica and L. × bella) — the shrubs that leaf out first in spring and crowd Pennsylvania woodland edges with a dense understory nothing native can grow under. The berries look generous, but they're junk food for birds compared to native fruit.
• Japanese barberry (Berberis thunbergii) — a spiny shrub sold for decades for its red foliage. It escapes into the woods, changes the soil chemistry, and — because it traps humidity underneath — has been tied to higher tick numbers where it takes over.
• Callery / Bradford pear (Pyrus calleryana) — introduced in the mid-20th century as a popular spring flowering tree. We've been regretting it ever since. It spreads aggressively through birds eating the fruit and poop-planting new trees wherever they go. On the bright side, this is one of the more satisfying invasives to take out. Just know a cut stump resprouts, so ask your Penn State Extension office about finishing the job.
• Burning bush (Euonymus alatus) — famous for its neon-red fall color, and that's exactly the problem: birds carry the seed into the woods, where it forms dense thickets that shade out everything native.
• Oriental bittersweet (Celastrus orbiculatus) — this vine is easy to spot in autumn because it makes red/orange fruit. You'll often see it on the sides of roadways, blanketing trees and choking out everything it can climb. The sheer weight can cause trees to uproot.
• Garlic mustard (Alliaria petiolata) — this stinky thug crowds other plants out by spreading a carpet of garlic-smelling weeds. They're not hard to pull, but get them before they seed, otherwise you'll just be helping them spread.
• Japanese stiltgrass (Microstegium vimineum) — a delicate-looking annual grass that carpets shady trailsides and floodplains, then collapses into a smothering thatch nothing native can push through.
• Common buckthorn (Rhamnus cathartica) — leafs out early and holds its leaves late, hogging the light on both ends of the season. Birds eat the berries, so the seeds travel far and fast.
• Tree-of-heaven (Ailanthus altissima) — a fast, foul-smelling tree that readily resprouts from roots and stumps, which is why simply cutting it down can make the problem worse. In Pennsylvania it's a double problem: it's the preferred host of the invasive spotted lanternfly.
• Purple loosestrife (Lythrum salicaria) — don't be fooled by their attractive purple flowering spires. They are lipstick on a very, very bad pig. Purple loosestrife can form dense stands in wetlands and displace native wetland vegetation.
• Poison hemlock (Conium maculatum) and wild parsnip (Pastinaca sativa) — two lookalikes of harmless roadside flowers with a nasty streak. Poison hemlock is toxic if ingested; wild parsnip's sap, plus sunlight, causes burns. Don't just yank either one — follow the recommended removal techniques.

Safety note: Giant hogweed, poison hemlock, and wild parsnip can burn or poison people and animals. Confirm identification and follow Pennsylvania/Extension guidance rather than handling them casually.

If you find one of these invasives already in the garden, the kindest thing for the land around you is to remove it. Your county Penn State Extension office can point you to the safe way.

Pennsylvania native plant and invasive species resources

A few authoritative places to dig deeper:

• Pennsylvania Department of Agriculture — the Controlled Plant and Noxious Weed Act lists (Class A, B, and C).
• Penn State Extension — region-specific planting and safe-removal guidance from your county office.
• Pennsylvania DCNR — native plant and invasive species information for Pennsylvania landscapes, including the state's invasive plant fact sheets.
• Pennsylvania Native Plant Society — native plant sales across the state and a list of native nurseries.
• Royal Botanic Gardens, Kew — World Checklist of Vascular Plants (WCVP) — the taxonomy and native-range source behind this page.

How Percy helps

Percy is the garden journal that remembers, so you can enjoy your garden. It's also a planner and a personalized assistant, and you just talk to it. It can identify plants, help you understand whether they're native or invasive where you live, suggest plants that support local wildlife, and remember what you planted and where.

When Percy identifies a plant or pest, it's region-aware. It knows that a plant can be a welcome native in one region and an aggressive invasive in another — so the same plant that earns a celebration in one garden earns a "get the gloves on" in another. It encourages environmentally responsible gardening by flagging invasives worth removing and celebrating natives.

You don't have to memorize any of this list. You just have to notice your garden and know you've got someone to ask. Percy keeps the rest and helps you tell natives from invasives.

Frequently asked questions

What plants are native to Pennsylvania? Pennsylvania natives include meadow and woodland wildflowers like New England aster, butterfly weed, wild bergamot, black-eyed Susan, cardinal flower, and blazing star, plus native trees like flowering dogwood, eastern redbud, and white oak. Native ranges here are verified against the World Checklist of Vascular Plants (Kew).

What are some of the best native plants for a Pennsylvania garden? Good choices include New England aster, butterfly weed, wild bergamot, cardinal flower, woodland phlox, spicebush, buttonbush, serviceberry, eastern redbud, and white oak. The best choice for a particular garden depends on sun, soil moisture, available space, and what wildlife you hope to support.

What native plants are best for Pennsylvania pollinators? Good Pennsylvania-native choices for pollinators include butterfly weed, wild bergamot, golden alexanders, cardinal flower, New England aster and native goldenrods. The best combination is one that provides blooms from spring through fall and matches the sun and moisture conditions in your garden.

Are all plants native to Pennsylvania suitable for every Pennsylvania garden? No. A plant can be native to Pennsylvania but still prefer conditions your particular garden doesn't have — the Philadelphia Piedmont, the Allegheny ridges, and the northern tier are very different places to garden. Sun, soil moisture, drainage, mature size, and elevation all matter.

What plants are invasive in Pennsylvania? Pennsylvania lists many under the Controlled Plant and Noxious Weed Act, including Japanese knotweed, mile-a-minute, Callery pear, Japanese barberry, burning bush, multiflora rose, bush honeysuckles, Oriental bittersweet, garlic mustard, and giant hogweed.

Is Callery (Bradford) pear invasive in Pennsylvania? Yes. Pennsylvania lists Callery pear (Pyrus calleryana), including Bradford pear, as a Class B noxious weed. It cannot legally be sold, transported, planted or otherwise propagated in Pennsylvania. Native flowering alternatives include eastern redbud, flowering dogwood and serviceberry.

How do I know if a plant is native or invasive where I live? Start with a confident identification, then check it against your specific region — status is regional, so a plant that's fine in one state can be a problem in another. Percy does this the region-aware way: when it identifies a plant, it flags invasives worth not spreading and celebrates the natives worth keeping.

Where can I buy native plants in Pennsylvania? Start with the Pennsylvania Native Plant Society, which keeps a statewide list of native nurseries and sales, and the spring plant sales DCNR runs at Ohiopyle, Gifford Pinchot and Kings Gap (usually late April into early May). Bowman's Hill Wildflower Preserve in New Hope sells natives only, and Choose Native Plants PA lets you filter by your yard's conditions, then shows where to buy each plant. Wherever you shop, check the tag for the botanical name: plenty of plants sold as "native" are cultivars bred for looks, and the straight species is usually what your local wildlife knows how to eat.

Is there a plant identification app that tells you if a plant is native or invasive? Yes — Percy does. Percy is the garden journal that remembers. When Percy identifies a plant, it also flags invasives worth removing and celebrates the natives, so you know not just what a plant is, but whether it belongs where you garden.

What plant app is best for supporting pollinators and local wildlife? The one that knows your region. Percy flags which of your plants are natives that feed local bees, butterflies, and birds — and which invasives are quietly starving them out — based on where you live and where your garden actually is.

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Native ranges: World Checklist of Vascular Plants, Royal Botanic Gardens, Kew (CC BY 4.0). Invasive and noxious-weed status: Pennsylvania Controlled Plant and Noxious Weed Act (Pennsylvania Department of Agriculture).