Native plants · Iowa

Native plants of Hamilton County

45 plant species are recorded as native to Iowa in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in Hamilton County by USDA PLANTS. 27 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

Hamilton County, Iowa

PLANTS records only 27 garden-ready natives here (under 30). County records are thin in some places; the Iowa list is a useful second check.

Native species
45 Typical Iowa county: 44 (median of 99 counties)
Garden-ready natives
27 Typical Iowa county: 24
Share by type (all 45 native species)
Percent of the 45 native species in each growth type
Tree 4% (2)
Shrub 2% (1)
Wildflower (forb) 20% (9)
Grass or grass-like 64% (29)
Vine 2% (1)
Fern 7% (3)

Grasses and grass-like plants make up the largest share of the native list (64%), followed by wildflowers (20%).

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 5a (2023 map).

The native plant list

Cold hardiness is estimated from each plant’s PLANTS minimum temperature. How we estimate it.

Garden-ready natives 27

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

Garden-ready native plants of Hamilton County, Iowa
PlantType HeightLight Water useHardy to
American vetch Vicia americana Vine 1.3 ft Sun Low Zone 3b
annual wildrice Zizania aquatica Grass or grass-like 9.8 ft Sun High Zone 10b
big bluestem Andropogon gerardii Grass or grass-like 6 ft Sun Low Zone 2b
Canada wildrye Elymus canadensis Grass or grass-like 3 ft Shade-tolerant Medium Zone 3a
field horsetail Equisetum arvense Fern 11 in Sun–part shade High Zone 3a
fowl bluegrass Poa palustris Grass or grass-like 4 ft Sun–part shade Medium Zone 3b
fowl mannagrass Glyceria striata Grass or grass-like 5.7 ft Shade-tolerant Medium Zone 3b
green needlegrass Nassella viridula Grass or grass-like 2 ft Sun Low Zone 3b
hairy grama Bouteloua hirsuta Grass or grass-like 6 in Sun Low Zone 3b
Indiangrass Sorghastrum nutans Grass or grass-like 6 ft Sun Medium Zone 3b
little bluestem Schizachyrium scoparium Grass or grass-like 3 ft Sun Low Zone 3b
marsh muhly Muhlenbergia racemosa Grass or grass-like 3 ft Shade-tolerant Medium Zone 3b
Mexican muhly Muhlenbergia mexicana Grass or grass-like 3 ft Sun–part shade Medium Zone 4a
peachleaf willow Salix amygdaloides Tree 60 ft Sun High Zone 4a
porcupinegrass Hesperostipa spartea Grass or grass-like 4 ft Sun Medium Zone 3b
prairie blazing star Liatris pycnostachya Wildflower (forb) 3.5 ft Sun Medium Zone 4a
prairie cordgrass Spartina pectinata Grass or grass-like 8 ft Sun High Zone 3b
prairie dropseed Sporobolus heterolepis Grass or grass-like 2.3 ft Sun–part shade Low Zone 3b
prairie Junegrass Koeleria macrantha Grass or grass-like 1.5 ft Shade-tolerant High Zone 3b
red mulberry Morus rubra Tree 70 ft Shade-tolerant Medium Zone 4a
rough bentgrass Agrostis scabra Grass or grass-like 2.5 ft Sun Medium Zone 3b
rufous bulrush Scirpus pendulus Grass or grass-like 4 ft Sun Medium Zone 3b
sideoats grama Bouteloua curtipendula Grass or grass-like 3 ft Sun Medium Zone 3a
slender wheatgrass Elymus trachycaulus Grass or grass-like 3 ft Sun Medium Zone 3b
smooth horsetail Equisetum laevigatum Fern 5 ft Sun Low Zone 3b
teal lovegrass Eragrostis hypnoides Grass or grass-like 4 in Sun High Zone 3b
water horsetail Equisetum fluviatile Fern 3 ft Sun High Zone 4a

Other native species recorded here 18

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.

  • bog yellowcress Rorippa palustris
  • bottlebrush sedge Carex hystericina
  • bulblet-bearing water hemlock Cicuta bulbifera
  • Canadian honewort Cryptotaenia canadensis
  • eastern bottlebrush grass Elymus hystrix
  • Heller's rosette grass Dichanthelium oligosanthes
  • hemlock waterparsnip Sium suave
  • Macoun's barley ×Elyhordeum macounii
  • northern sweetgrass Hierochloe hirta
  • Nuttall's prairie parsley Polytaenia nuttallii
  • prairie groundsel Packera plattensis
  • prairie rose Rosa arkansana
  • puffsheath dropseed Sporobolus neglectus
  • slender wedgescale Sphenopholis intermedia
  • smallflower fumewort Corydalis micrantha
  • western silver aster Symphyotrichum sericeum
  • whitehair rosette grass Dichanthelium villosissimum
  • witchgrass Panicum capillare
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.

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, Hamilton County and Iowa
MeasureHamilton CountyTypical countyStatewide
Native species 45 44 1,374
Garden-ready natives 27 24 496
Tree 2 — 110
Shrub 1 — 72
Wildflower (forb) 9 — 779
Grass or grass-like 29 — 298
Vine 1 — 55
Fern 3 — 60

Neighboring counties

Counties that share a ZIP code with Hamilton County.

Look up another ZIP

Matches your ZIP to the county it mostly lies in, then lists the plants recorded as native to your state (Kew’s World Checklist and USDA PLANTS) and recorded in that county by USDA PLANTS.

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
Hamilton County (county FIPS 19079), Iowa. 45 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.