Native plants · Oklahoma

Native plants of Harmon County

118 plant species are recorded as native to Oklahoma in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in Harmon County by USDA PLANTS. 48 of them have growing records you can filter by light, moisture, height and estimated cold hardiness.

County summary · USDA PLANTS and Kew WCVP

Harmon County, Oklahoma

Native species: 118 Typical Oklahoma county: 203 (median of 77 counties)
Garden-ready natives: 48 Typical Oklahoma county: 80
Share by type (all 118 native species): Percent of the 118 native species in each growth type

Tree 8% (10)
Shrub 6% (7)
Wildflower (forb) 69% (81)
Grass or grass-like 16% (19)
Fern <1% (1)

Wildflowers make up the largest share of the native list (69%), followed by grasses and grass-like plants (16%).

Recorded native ranges can include long-established populations that spread from gardens; check your state’s native plant society list for local guidance. How native status is decided.

ZIP codes mainly in this county fall in USDA hardiness zone 7b (2023 map).

The native plant list

Garden-ready natives 48

Native species with PLANTS growing records (height, light, moisture, minimum temperature). “—” means PLANTS has no value.

Garden-ready native plants of Harmon County, Oklahoma
Plant	Type	Height	Light	Water use	Hardy to
alkali sacaton Sporobolus airoides	Grass or grass-like	3 ft	Sun	Low	Zone 3b
American elm Ulmus americana	Tree	120 ft	Sun–part shade	High	Zone 2b
American licorice Glycyrrhiza lepidota	Wildflower (forb)	4 ft	Sun–part shade	High	Zone 3b
big bluestem Andropogon gerardii	Grass or grass-like	6 ft	Sun	Low	Zone 2b
black willow Salix nigra	Tree	100 ft	Sun	High	Zone 1b
broadleaf cattail Typha latifolia	Wildflower (forb)	5 ft	Sun–part shade	High	Zone 3b
broom snakeweed Gutierrezia sarothrae	Shrub	1.5 ft	Sun	Medium	Zone 3b
Canadian horseweed Conyza canadensis	Wildflower (forb)	5 ft	Sun	Medium	Zone 12b
Chickasaw plum Prunus angustifolia	Tree	12 ft	Sun	Medium	Zone 4b
common hackberry Celtis occidentalis	Tree	60 ft	Shade-tolerant	Low	Zone 2b
coon's tail Ceratophyllum demersum	Wildflower (forb)	—	Sun–part shade	High	Zone 3b
cosmopolitan bulrush Bolboschoenus maritimus	Grass or grass-like	3.2 ft	Sun	Medium	Zone 5a
dotted blazing star Liatris punctata	Wildflower (forb)	2 ft	Sun	Medium	Zone 3a
eastern cottonwood Populus deltoides	Tree	190 ft	Sun	High	Zone 3a
flatstem spikerush Eleocharis compressa	Grass or grass-like	2 ft	Sun	High	Zone 4a
fourwing saltbush Atriplex canescens	Shrub	4 ft	Sun	Medium	Zone 3a
golden currant Ribes aureum	Shrub	10 ft	Sun–part shade	Low	Zone 3b
green prairie coneflower Ratibida tagetes	Wildflower (forb)	1 ft	Sun	Low	Zone 4b
hairy grama Bouteloua hirsuta	Grass or grass-like	6 in	Sun	Low	Zone 3b
honey mesquite Prosopis glandulosa	Tree	50 ft	Sun	Low	Zone 6a
Indian blanket Gaillardia pulchella	Wildflower (forb)	2 ft	Sun	Medium	Zone 10b
little barley Hordeum pusillum	Grass or grass-like	1.2 ft	Sun	Medium	Zone 10b
little walnut Juglans microcarpa	Tree	20 ft	Sun	Medium	Zone 7a
lyreleaf greeneyes Berlandiera lyrata	Wildflower (forb)	4 ft	Sun	Low	Zone 5a
Nuttall's povertyweed Monolepis nuttalliana	Wildflower (forb)	10 in	Sun	Medium	Zone 12a
post oak Quercus stellata	Tree	60 ft	Sun	Medium	Zone 4a
purple prairie clover Dalea purpurea	Wildflower (forb)	3 ft	Sun	Medium	Zone 3b
purple threeawn Aristida purpurea	Grass or grass-like	1.4 ft	Sun	Low	Zone 4a
roughfruit amaranth Amaranthus tuberculatus	Wildflower (forb)	6.6 ft	Sun	High	Zone 4a
salt heliotrope Heliotropium curassavicum	Wildflower (forb)	1.2 ft	Sun	Medium	Zone 4b
sand dropseed Sporobolus cryptandrus	Grass or grass-like	3 ft	Sun	Low	Zone 3b
sandbar willow Salix interior	Tree	30 ft	Sun	—	Zone 1a
scarlet globemallow Sphaeralcea coccinea	Wildflower (forb)	1.5 ft	Sun	Low	Zone 5a
sideoats grama Bouteloua curtipendula	Grass or grass-like	3 ft	Sun	Medium	Zone 3a
skunkbush sumac Rhus trilobata	Shrub	4 ft	Sun–part shade	Low	Zone 2a
soapweed yucca Yucca glauca	Shrub	1 ft	Sun	Low	Zone 4b
spreading alkaliweed Cressa truxillensis	Wildflower (forb)	10 in	Sun	Medium	Zone 6a
squirreltail Elymus elymoides	Grass or grass-like	1.5 ft	Sun	Low	Zone 3a
sugarberry Celtis laevigata	Tree	80 ft	Shade-tolerant	High	Zone 5a
sweetscent Pluchea odorata	Wildflower (forb)	4.9 ft	Sun	Medium	Zone 6a
tanseyleaf tansyaster Machaeranthera tanacetifolia	Wildflower (forb)	2 ft	Sun	Medium	Zone 4a
tobosagrass Pleuraphis mutica	Grass or grass-like	2.3 ft	Sun	Low	Zone 7b
Torrey's rush Juncus torreyi	Grass or grass-like	3.1 ft	Sun	Medium	Zone 3b
upright prairie coneflower Ratibida columnifera	Wildflower (forb)	3.1 ft	Sun	Medium	Zone 3a
white prairie clover Dalea candida	Wildflower (forb)	2 ft	Sun–part shade	Medium	Zone 3b
white sagebrush Artemisia ludoviciana	Wildflower (forb)	3 ft	Sun	Low	Zone 4a
woolly locoweed Astragalus mollissimus	Wildflower (forb)	2 ft	Sun	Low	Zone 4b
woolly plantain Plantago patagonica	Wildflower (forb)	6 in	Sun	Low	Zone 12b

Other native species recorded here 70

PLANTS has no growing records for these, so light, moisture, height and zone filters cannot include them. Many are wild species seldom sold by nurseries.

American star-thistle Centaurea americana
annual marsh elder Iva annua
Baldwin's ironweed Vernonia baldwinii
buffalobur nightshade Solanum rostratum
Carolina canarygrass Phalaris caroliniana
Carolina larkspur Delphinium carolinianum
catchfly prairie gentian Eustoma exaltatum
chickenthief Mentzelia oligosperma
common yellow oxalis Oxalis stricta
Cuman ragweed Ambrosia psilostachya
curlytop knotweed Polygonum lapathifolium
cutleaf evening primrose Oenothera laciniata
Dakota mock vervain Glandularia bipinnatifida
diamond-flowers Stenaria nigricans
Drummond's false pennyroyal Hedeoma drummondii
dwarf horseweed Conyza ramosissima
Engelmann's daisy Engelmannia peristenia
fall witchgrass Digitaria cognata
false buffalograss Munroa squarrosa
flatspine stickseed Lappula occidentalis
hogwort Croton capitatus
Hopi tea greenthread Thelesperma megapotamicum
kiss me quick Portulaca pilosa
lacy tansyaster Machaeranthera pinnatifida
lemon beebalm Monarda citriodora
mat sandbur Cenchrus longispinus
narrowleaf four o'clock Mirabilis linearis
narrowleaf stoneseed Lithospermum incisum
Nuttall's sensitive-briar Mimosa nuttallii
Pennsylvania pellitory Parietaria pensylvanica
pineland threeseed mercury Acalypha ostryifolia
prairie broomweed Amphiachyris dracunculoides
prairie sandmat Chamaesyce missurica
prairie spiderwort Tradescantia occidentalis
prairie sunflower Helianthus petiolaris
prairie tea Croton monanthogynus
purple cliffbrake Pellaea atropurpurea
redseed plantain Plantago rhodosperma
redwhisker clammyweed Polanisia dodecandra
ribseed sandmat Chamaesyce glyptosperma
rush skeletonplant Lygodesmia juncea
saline saltbush Atriplex subspicata
sand sagebrush Artemisia filifolia
sandhill amaranth Amaranthus arenicola
scarlet beeblossom Oenothera suffrutescens
scrambled eggs Corydalis aurea
shaggy dwarf morning-glory Evolvulus nuttallianus
showy evening primrose Oenothera grandis
silverleaf nightshade Solanum elaeagnifolium
silverscale saltbush Atriplex argentea
slender yellow woodsorrel Oxalis dillenii
slimleaf milkweed Asclepias stenophylla
sneezeweed Helenium amarum
snow on the mountain Euphorbia marginata
snowball sand verbena Abronia fragrans
southern annual saltmarsh aster Symphyotrichum divaricatum
spinystar Escobaria vivipara
spiral ditchgrass Ruppia cirrhosa
spotted beebalm Monarda punctata
spotted sandmat Chamaesyce maculata
stemless evening primrose Oenothera triloba
stemless Townsend daisy Townsendia exscapa
Texas bluegrass Poa arachnifera
Texas signalgrass Urochloa texana
tumblegrass Schedonnardus paniculatus
velvetweed Oenothera curtiflora
warty caltrop Kallstroemia parviflora
warty spurge Euphorbia spathulata
whitest evening primrose Oenothera albicaulis
woolly tidestromia Tidestromia lanuginosa

Compared with Oklahoma

The typical county is the median of the 77 Oklahoma counties with PLANTS county records; the statewide figure counts every species native anywhere in the state. More species is not better or worse: counties differ in size, habitat and how thoroughly they have been surveyed.

Native species counts, Harmon County and Oklahoma
Measure	Harmon County	Typical county	Statewide
Native species	118	203	1,513
Garden-ready natives	48	80	535
Tree	10	—	130
Shrub	7	—	63
Wildflower (forb)	81	—	849
Grass or grass-like	19	—	341
Vine	0	—	85
Fern	1	—	45

Neighboring counties

Counties that share a ZIP code with Harmon County.

Greer County, OK 82 garden-ready
Jackson County, OK 43 garden-ready

Source & data date

Source: USDA NRCS PLANTS Database: county distribution records, native status and plant characteristics. CC0 (public domain dedication, per the data.gov catalog record).; Kew’s World Checklist of Vascular Plants (WCVP): native or introduced status by state. CC BY 3.0.; USGS US-RIIS (ver. 2.0): species listed as introduced are excluded. CC0.
Citation: USDA, NRCS. 2026. The PLANTS Database (https://plants.usda.gov, 11/04/2026). National Plant Data Team, Greensboro, NC USA.; Govaerts R. (ed.) (2026). WCVP: World Checklist of Vascular Plants. Facilitated by the Royal Botanic Gardens, Kew. Data file dated 2026-06-04, http://sftp.kew.org/pub/data-repositories/WCVP/ (retrieved 2026-11-04). Paper: Govaerts R. et al. (2021) The World Checklist of Vascular Plants, a continuously updated resource for exploring global plant diversity. Scientific Data 8, 215.
Data date: Retrieved from PLANTS on November 4, 2026; WCVP data file dated June 4, 2026.
Zones: USDA Plant Hardiness Zone Map (2023) ZIP table: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 3, 2026. Plant zones on this site are our estimate, not the official map.
Scope: Harmon County (county FIPS 40057), Oklahoma. 118 native species from PLANTS county distribution records; garden-ready = species with a PLANTS characteristics record.
Method: A species is listed when it is recorded as native to the state in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in the county by USDA PLANTS. Species PLANTS labels both native and introduced are listed separately. Full method · All sources

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