red tasselflower (Emilia sonchifolia), photographi

Can I Grow Red Tasselflower in Indiana?

USDA Zones 5b-7b · Plant zone range 8-11

Unlikely — Zone Mismatch

red tasselflower (zones 8-11) does not overlap with Indiana's zone range (5b-7b). Growing outdoors is unlikely without significant protection.

One zone short — what would close it

Red Tasselflower is hardy to zone 8, and the warmest ground in Indiana is zone 7 — 1 zone short. Planted in open ground it will not survive a Indiana winter. To grow it here, grow red tasselflower in a hoop house or unheated greenhouse — its modeled 1.5-zone lift covers this gap.

A hoop house or unheated greenhouse is the lift this needs. How a greenhouse changes what you can grow →

Zone math from 8-11 (plant) against 5-7 (Indiana). Lift modeled by crop_engine.GREENHOUSE_ZONE_MODIFIER_BY_SUBTYPE['hoop_house'] (+1.5 zones) via api/fast_sections.py Unlock Engine v2.

Red Tasselflower in Indiana — the short answer

Red Tasselflower in Indiana: hardy in zones 8–11, full sun, against a state median of ~209 frost-free days.

Plant zones
8-11
Manual horticultural correction (source not retained); NC State Extension and Missouri Botanical Garden, with the remaining rows from other published sources or Growable Ground compilation
Indiana zones
5b-7b
USDA PHZM 2023
Frost window
Apr 4 - Apr 9 – Oct 30 - Nov 4
NOAA RCC ACIS 1991-2020, 28°F
Shortest county season
191 days
NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze

Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS and university Extension sources — per-field provenance varies and is published with the dataset.

Score your parcel · free

Your yard isn't the whole zone.

Red Tasselflower is grown as an annual, so your winter zone isn't the deciding factor — your frost-free window is. A typical Indiana site runs ~209 frost-free days, but that is a state median, not your yard: slope, trees, and low spots move the last-frost date across a single parcel. Enter your address and we'll score red tasselflower against your land's actual frost dates, sun, and soil.

We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.

No card required · your full report in seconds

Indiana is not one climate

A single Indiana answer averages 92 counties whose growing seasons are 41 days apart — from 191 frost-free days in Steuben County to 232 in Posey County. Which end of that your land sits nearer changes what red tasselflower can finish before the first hard freeze.

191 daysSteuben County232 daysPosey County

The middle half of 92 counties runs 203214 days, with a median of 209 days — a 41-day span end to end.

Measured across 92 Indiana counties. NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze. Quartiles are order statistics — every figure shown is a value a real county recorded, not an interpolation. Your own site sits somewhere inside this range; a parcel report resolves where.

Where Red Tasselflower Stands in Indiana

Red Tasselflower is rated for zones 811 — a cold floor USDA puts at 10 to 20°F. No Indiana county sits inside it, so in open ground this is a grown-under-cover plant here rather than a bed plant — which is a statement about Indiana winters, not about red tasselflower.

Below the zone 8 floor

92 counties

3 of 92 shown

Winter cold is the limit here — the same plant works in a container that comes under cover.

County hardiness zones: USDA Plant Hardiness Zone Map (PHZM) 2023, per county. A zone is a 10°F band of average annual extreme minimum temperature, so the floor above is the band the plant's rating denotes, not a single measured kill point. Slope, shelter and cold-air drainage routinely move a site half a zone either way from its county figure — which is the part only your address resolves.

Zone Comparison

Red Tasselflower Needs

  • USDA Zones: 8-11
  • Frost-Free Days: 90+
  • Sun: Full Sun
  • Picking window: ~90 days of harvest

Indiana Has

  • USDA Zones: 5b-7b
  • Last Hard Freeze (28°F): Apr 4 - Apr 9
  • First Hard Freeze (28°F): Oct 30 - Nov 4
  • Annual Rainfall: 36-46 inches
  • Common Soils: Silt loam, Clay loam, Glacial till

Plant Zone Range (zones 8-11)

8a
11b
3a (Cold)13b (Hot)

Preferred Soil pH

3.5 (Acidic)7.0 (Neutral)9.0 (Alkaline)
Highlighted range: pH 4.07.0

Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS, and university Extension sources — per-field provenance varies and is published with the dataset. State data: USDA ARS PHZM 2023, NOAA Climate Normals, NRCS SSURGO.

When to Plant Red Tasselflower in Indiana

The frost window

Across Indiana, the last spring hard freeze (28°F) clears between Apr 4 and Apr 9, and the first fall hard freeze lands between Oct 30 and Nov 4 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 204-day window you can count on — up to 214 days on a mild site in a kind year. That marks the hard freeze, not the last light frost, so tender transplants usually wait another 2-3 weeks.

When to start the seed

Those dates are when red tasselflower goes out, not when it starts. It is sown under cover about 6 weeks ahead, so counting back from Indiana's late-side last freeze of Apr 9 is what fixes your sowing date — and a yard that clears frost earlier than the state's late date starts earlier still.

Timing tuned to sub-state frost dates — Steuben County, not the statewide average.

Frost window: NOAA Climate Normals 1991-2020. Plant timing fields: Growable Ground Plant Database — frost-free days from FAO ECOCROP, days to harvest from university Extension production guides, and growing-degree-day and chill-hour minimums that are compilation estimates rather than published figures. Your site's own frost dates can run earlier or later than the state range — a parcel report pins them down.

Growing Season Fit

The zone check says red tasselflower does not survive a Indiana winter in the ground. The season figures below measure a different question — whether it could finish a season here at all — and they only bear on Indiana under protection.

Frost-free days

Red Tasselflower wants 90+ frost-free days; a typical Indiana site sees ~209 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves comfortable headroom for succession planting.

GDD and chill-hour figures are computed from PRISM 1991-2020 monthly climate normals; frost-free days from NOAA Regional Climate Centers ACIS, 1991-2020. Each is the state median across its counties (P25/P75 span the within-state spread). Hardiness-zone range is USDA PHZM 2023.

Soil + Drainage Fit

Red Tasselflower tolerates a wide pH range (pH 4-7) — 3 units, acid ground through alkaline — so soil acidity is rarely what limits it in Indiana. A soil test is still worth having, but for what else it tells you about this site, not to clear this plant. It will grow across that whole span, but it does best between pH 4.5 and 6.5 — worth knowing before you decide whether a Indiana soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Indiana site is heavier clay or sits in a low spot, raised beds or amendment with compost solve it.

Your land, not the state average

SSURGO maps about 37.8% of Indiana as poorly or somewhat-poorly drained, and the class flips parcel to parcel. Red Tasselflower sits mid-range for drought tolerance, so either extreme can cost you — your soil map unit, not the state average, is the real answer.

Check your parcel → Source: USDA NRCS SSURGO.

Plant pH requirements: FAO ECOCROP and USDA PLANTS, with the remaining rows from other published sources or Growable Ground compilation. Drainage: FAO ECOCROP, with the remaining rows from other published sources or Growable Ground compilation. Indiana soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.

What Else to Consider for Red Tasselflower in Indiana

Zone compatibility tells you about winter cold survival — but Indiana growers also need to think about:

Heavy clay soils limit drainage in many areas

Late spring frosts through early May

Hot humid summers promote blight and mildew

Growing red tasselflower here specifically

Red Tasselflower roots run medium and prefer pH 4.0–7.0, but drainage comes first here: SSURGO maps about 37.8% of Indiana as poorly or somewhat-poorly drained, and wet ground rots its roots before pH ever matters.

Plant red tasselflower on a raised, gravel-amended berm so water drains fast and the roots stays dry. How to handle it →

What to actually do about these — and the constraints that apply to every Indiana grower, not just red tasselflower — is covered on the Indiana growing guide.

Timing shifts within Indiana

Indiana isn't one climate. In Steuben County, the last hard freeze (28°F) holds until about Apr 18 — roughly 11 days later than the recorded state median — so plant red tasselflower to your county's window, not the statewide date.

Red Tasselflower needs about 90 days of frost-free season to complete its cycle. Even Steuben County — Indiana’s shortest season at 191 frost-free days — clears that by 101 days, so season length isn’t the constraint anywhere in Indiana. What varies is your own parcel.

County last-freeze dates and frost-free day counts: NOAA Regional Climate Centers ACIS (1991-2020), county 28°F freeze (earlier than the folk 32°F "last frost"). Red Tasselflower's 90-day requirement: USDA PLANTS / Growable Ground plant database (minimum frost-free days). A parcel report resolves your address's own frost dates.

Pollinator + Wildlife Value

Red Tasselflower draws honeybees and native bees (low value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, red tasselflower can only work that bloom inside Indiana's frost window — roughly 209 days, opening after the last 28°F freeze (Apr 4 - Apr 9) and closing at the first (Oct 30 - Nov 4), per NOAA Regional Climate Centers ACIS, 1991-2020.

Recommended Red Tasselflower Varieties for Indiana

Indiana publishes no state variety trial for red tasselflower, so we won't invent a "best for Indiana" list. Choose types rated to your USDA hardiness zone (5b-7b), and confirm winter survival and drainage against your own parcel.

Indiana Cooperative Extension

For Indiana-specific cultivar recommendations, planting calendars, and pest pressure for red tasselflower, the canonical source is Purdue Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.

Is Red Tasselflower native to Indiana?

No — the USDA PLANTS Database lists Red Tasselflower as introduced rather than native in the Lower 48, so it is not part of Indiana's native flora. It grows here as a garden plant; pairing it with a few Indiana natives keeps local pollinators fed too.

Looking for plants that belong here? The Indiana growing guide lists USDA-documented natives for the state.

Native-range data: USDA PLANTS Database state-distribution records, accessed 2026-07-01.

Common Questions About Growing Red Tasselflower in Indiana

When can I plant Red Tasselflower in Indiana?

Indiana's last spring hard freeze (28°F) clears between Apr 4 and Apr 9, and the first fall hard freeze lands between Oct 30 and Nov 4 (NOAA Regional Climate Centers ACIS, 1991-2020). Time outdoor planting to after the last hard freeze for your specific site — a further two to three weeks for anything tender — and count back from those dates for transplant scheduling.

What hardiness zone is Red Tasselflower grown in across Indiana?

Indiana spans USDA hardiness zones 5b-7b (USDA ARS PHZM 2023). Red Tasselflower carries a range of zones 8-11, so the overlap zones are where outdoor growing is most reliable.

How many frost-free days does a typical Indiana site have?

A typical Indiana site sees ~209 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Red Tasselflower needs 90+ frost-free days, so check whether your local microclimate runs above or below the state average before settling on a planting date. In cooler counties like Steuben, the freeze-free season runs shorter than the state average, so verify your own county's window.

Is Red Tasselflower native to Indiana?

No — the USDA PLANTS Database lists Red Tasselflower as introduced rather than native in the Lower 48, so it is not part of Indiana's native flora. It grows here as a garden plant; pairing it with a few Indiana natives keeps local pollinators fed too.

How should I amend the soil for Red Tasselflower in Indiana?

Red Tasselflower tolerates pH 4-7 and well (dry spells) drainage (FAO ECOCROP). That is a 3-unit span, acid ground through alkaline, so pH is rarely what limits this plant on a Indiana site — amend for drainage and organic matter first.

Will Red Tasselflower actually grow on my specific land in Indiana?

State-level zone + climate data is a sketch. A Growable Ground parcel report scores red tasselflower against your address's exact soil pH, drainage, sun, and frost-date data drawn from USDA SSURGO, NOAA, and PRISM — not state averages.

Free Report

Check your specific parcel in Indiana

State-level data is a sketch. Your Growable Ground report scores red tasselflower against your parcel's exact soil, sun, drainage, and frost data — not zone averages.

Three things about your lot that Indiana red tasselflower averages can't show:

Your soil pHYour frost-free days — Indiana averages 209Your sun & shade

We read public map data around Indiana — soil, climate, flood, and parcel records. How we handle your address.

25+ data sources read at your address, not the Indiana red tasselflower average

Explore More

Explore Indiana county by county

Indiana carries 92 counties with their own USDA zone — a sample of the growing pages for red tasselflower there:

Where else red tasselflower grows

Red Tasselflower's zone band crosses state lines — these are the states closest to Indiana in winter climate where it also has a page, plus the far ends of its range. Each one re-answers the question with that state's own record.

More to grow in Indiana

Indiana has a growing page for 893 plants — a rotating sample of the rest of the shelf.

Analysis by the Growable Ground research team, grounded in USDA PLANTS, USDA NRCS SSURGO, NOAA Climate Normals (1991-2020), and named Cooperative Extension sources. How we know →

Cite this dataset

Kirchick, M. (2026). Growable Ground Plant Database [Data set]. Zenodo. https://doi.org/10.5281/zenodo.21435643

Licensed CC BY-NC 4.0. DOI 10.5281/zenodo.21435643

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