Native plants · Iowa

Native plants of Clayton County

61 plant species are recorded as native to Iowa in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in Clayton County by USDA PLANTS. 24 of them have growing records you can filter by light, moisture, height and estimated cold hardiness. 1 more species is listed as both native and introduced and kept in a separate section.

County summary · USDA PLANTS and Kew WCVP

Clayton County, Iowa

PLANTS records only 24 garden-ready natives here (under 30). County records are thin in some places; the Iowa list is a useful second check.

Native species: 61 Typical Iowa county: 44 (median of 99 counties)
Garden-ready natives: 24 Typical Iowa county: 24
Share by type (all 61 native species): Percent of the 61 native species in each growth type

Tree 5% (3)
Wildflower (forb) 41% (25)
Grass or grass-like 30% (18)
Vine 3% (2)
Fern 21% (13)

Wildflowers make up the largest share of the native list (41%), followed by grasses and grass-like plants (30%).

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 zones 4b to 5a (2023 map).

The native plant list

Garden-ready natives 24

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

Garden-ready native plants of Clayton County, Iowa
Plant	Type	Height	Light	Water use	Hardy to
American bellflower Campanulastrum americanum	Wildflower (forb)	6 ft	Shade-tolerant	Medium	Zone 12b
arctic brome Bromus kalmii	Grass or grass-like	3 ft	Shade-tolerant	Low	Zone 4a
blackeyed Susan Rudbeckia hirta	Wildflower (forb)	1 ft	Sun	Medium	Zone 5a
boxelder Acer negundo	Tree	60 ft	Shade-tolerant	Medium	Zone 2b
Canada wildrye Elymus canadensis	Grass or grass-like	3 ft	Shade-tolerant	Medium	Zone 3a
cardinalflower Lobelia cardinalis	Wildflower (forb)	5.9 ft	Shade-tolerant	Low	Zone 4a
chinquapin oak Quercus muehlenbergii	Tree	70 ft	Sun	Medium	Zone 4a
crested woodfern Dryopteris cristata	Fern	1.6 ft	Shade-tolerant	High	Zone 4a
field horsetail Equisetum arvense	Fern	11 in	Sun–part shade	High	Zone 3a
halberdleaf rosemallow Hibiscus laevis	Wildflower (forb)	8 ft	Sun–part shade	High	Zone 6a
nodding fescue Festuca subverticillata	Grass or grass-like	3 ft	Sun–part shade	Medium	Zone 3a
northern maidenhair Adiantum pedatum	Fern	1.3 ft	Shade-tolerant	Medium	Zone 3b
pinnate prairie coneflower Ratibida pinnata	Wildflower (forb)	4 ft	Sun	Medium	Zone 3b
prairie dropseed Sporobolus heterolepis	Grass or grass-like	2.3 ft	Sun–part shade	Low	Zone 3b
rattlesnake fern Botrychium virginianum	Fern	1.4 ft	Shade-tolerant	Medium	Zone 3b
sandbar willow Salix interior	Tree	30 ft	Sun	—	Zone 1a
swamp milkweed Asclepias incarnata	Wildflower (forb)	4.9 ft	Sun	High	Zone 3b
threelobe beggarticks Bidens tripartita	Wildflower (forb)	3.5 ft	Sun–part shade	High	Zone 12a
threepetal bedstraw Galium trifidum	Vine	10 in	Sun–part shade	High	Zone 3b
Virginia wildrye Elymus virginicus	Grass or grass-like	2.5 ft	Shade-tolerant	Medium	Zone 4b
western wheatgrass Pascopyrum smithii	Grass or grass-like	2 ft	Sun	Medium	Zone 3a
wild bergamot Monarda fistulosa	Wildflower (forb)	4.9 ft	Sun–part shade	High	Zone 4a
winter bentgrass Agrostis hyemalis	Grass or grass-like	3.5 ft	Sun–part shade	High	Zone 4a
woodland muhly Muhlenbergia sylvatica	Grass or grass-like	3 ft	Sun–part shade	Medium	Zone 4b

Other native species recorded here 37

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.

Adam and Eve Aplectrum hyemale
bearded shorthusk Brachyelytrum erectum
bigbract verbena Verbena bracteata
blackseed ricegrass Patis racemosa
bluejacket Tradescantia ohiensis
bluntlobe cliff fern Woodsia obtusa
earlyleaf brome Bromus latiglumis
eastern bottlebrush grass Elymus hystrix
false melic Schizachne purpurascens
fire on the mountain Euphorbia cyathophora
hairy woodland brome Bromus pubescens
Heller's rosette grass Dichanthelium oligosanthes
hoary verbena Verbena stricta
Kalm's hawkweed Hieracium kalmii
lesser yellow lady's slipper Cypripedium parviflorum
meadow horsetail Equisetum pratense
Mexican Mosquito Fern Azolla microphylla
northern selaginella Selaginella rupestris
poverty oatgrass Danthonia spicata
prairie ironweed Vernonia fasciculata
purple meadow-rue Thalictrum dasycarpum
red columbine Aquilegia canadensis
rope dodder Cuscuta glomerata
sensitive fern Onoclea sensibilis
slender lipfern Cheilanthes feei
slender wedgescale Sphenopholis intermedia
smooth cliffbrake Pellaea glabella
smooth oxeye Heliopsis helianthoides
spinulose woodfern Dryopteris carthusiana
swamp verbena Verbena hastata
tall blazing star Liatris aspera
threeflower melicgrass Melica nitens
walking fern Asplenium rhizophyllum
western silver aster Symphyotrichum sericeum
white rattlesnakeroot Prenanthes alba
white vervain Verbena urticifolia
whorled milkweed Asclepias verticillata

Also listed as native and introduced here 1

PLANTS labels these species both native and introduced in this state: some forms are native and others were brought in from elsewhere. Most gardeners should choose plants from the main list.

climbing false buckwheatPolygonum scandens

Compared with Iowa

The typical county is the median of the 99 Iowa 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, Clayton County and Iowa
Measure	Clayton County	Typical county	Statewide
Native species	61	44	1,374
Garden-ready natives	24	24	496
Tree	3	—	110
Shrub	0	—	72
Wildflower (forb)	25	—	779
Grass or grass-like	18	—	298
Vine	2	—	55
Fern	13	—	60

Neighboring counties

Counties that share a ZIP code with Clayton County.

Allamakee County, IA 37 garden-ready
Delaware County, IA 8 garden-ready
Dubuque County, IA 12 garden-ready
Fayette County, IA 13 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: Clayton County (county FIPS 19043), Iowa. 61 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

Independent reference site. No government affiliation or endorsement.