Unlikely — Zone Mismatch
pickerel weed (zones 10-12) does not overlap with Maryland's zone range (5b-8a). Growing outdoors is unlikely without significant protection.
2 zones short — what would close it
Pickerel Weed is hardy to zone 10, and the warmest ground in Maryland is zone 8 — 2 zones short. Planted in open ground it will not survive a Maryland winter. To grow it here, grow pickerel weed in an earth-sheltered greenhouse — its modeled 2.5-zone lift covers this gap.
An earth-sheltered greenhouse is the lift this needs. How a greenhouse changes what you can grow →
Zone math from 10-12 (plant) against 6-8 (Maryland). Lift modeled by crop_engine.GREENHOUSE_ZONE_MODIFIER_BY_SUBTYPE['earth_sheltered'] (+2.5 zones) via api/fast_sections.py Unlock Engine v2.
Pickerel Weed in Maryland — the short answer
Pickerel Weed in Maryland: hardy in zones 10–12, full sun, against a state median of ~238 frost-free days.
- Plant zones
- 10-12
- 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
- Maryland zones
- 5b-8a
- USDA PHZM 2023
- Frost window
- Mar 18 - Mar 29 – Nov 11 - Nov 27
- NOAA RCC ACIS 1991-2020, 28°F
- Shortest county season
- 190 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.
Your yard isn't the whole zone.
Maryland spans zones 5b-8a, but your yard sits in exactly one — and slope, tree cover, and cold-air pockets nudge it further. Enter your address and we'll score pickerel weed against your parcel's actual hardiness, soil, and sun.
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
Maryland is not one climate
Maryland’s winter-low ladder runs across 24 counties, from zone 6 in Garrett County to zone 8 in Talbot County. That is 20°F between the two counties’ average coldest night — the difference between pickerel weed overwintering in the ground and coming under cover.
The middle half of 24 counties runs 7.5–7.5 zones, with a median of 7.5 zones — a 2-zone span end to end.
Measured across 24 Maryland counties. USDA PHZM 2023, per county. 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 Pickerel Weed Stands in Maryland
Pickerel Weed is rated for zones 10–12 — a cold floor USDA puts at 30 to 40°F. No Maryland 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 Maryland winters, not about pickerel weed.
Below the zone 10 floor
24 counties
- Garrett County · zone 6a
- Allegany County · zone 7a
- Carroll County · zone 7a
3 of 24 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
Pickerel Weed Needs
- USDA Zones: 10-12
- Frost-Free Days: 90+
- Sun: Full Sun
- Picking window: ~60 days of harvest
Maryland Has
- USDA Zones: 5b-8a
- Last Hard Freeze (28°F): Mar 18 - Mar 29
- First Hard Freeze (28°F): Nov 11 - Nov 27
- Annual Rainfall: 36-48 inches
- Common Soils: Silt loam, Clay, Sandy loam (Eastern Shore)
Plant Zone Range (zones 10-12)
Preferred Soil pH
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 Pickerel Weed in Maryland
The frost window
Across Maryland, the last spring hard freeze (28°F) clears between Mar 18 and Mar 29, and the first fall hard freeze lands between Nov 11 and Nov 27 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 227-day window you can count on — up to 254 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.
Winter standing
Maryland runs as cold as USDA zone 5, and no sourced winter-hardiness floor is on record for pickerel weed, so this page does not state whether it overwinters here — and gives no fall establishment date on the strength of a guess. Whether pickerel weed is a permanent planting or a replant-every-spring crop for you turns on your own zone within Maryland; check its hardiness range against that before treating it as long-lived ground.
Timing tuned to sub-state frost dates — Garrett 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 pickerel weed does not survive a Maryland 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 Maryland under protection.
Frost-free days
Pickerel Weed wants 90+ frost-free days; a typical Maryland site sees ~238 (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
Pickerel Weed tolerates a wide pH range (pH 4-7) — 3 units, acid ground through alkaline — so soil acidity is rarely what limits it in Maryland. 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 5 and 6.5 — worth knowing before you decide whether a Maryland soil test result is a problem or just a number. Drainage requirement: poorly (saturated >50% of year). A soil-survey lookup (NRCS SSURGO) flags whether your specific site matches.
Your land, not the state average
Maryland's soils run mostly silt loam, but SSURGO maps the series, texture, and drainage under your exact parcel. Pickerel Weed needs about 19 inches of workable depth, so it is that horizon — not the surface — you are testing for. That map unit, not the state average, decides how pickerel weed performs.
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. Maryland soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.
Before you plant pickerel weed for food
Anything you grow to eat takes up what is in the ground it grows in, so what is on record near you is worth knowing before pickerel weed goes in. What follows is Maryland’s documented federal record at state scale — a screening signal, not a soil test, and not a statement about any one lot.
Safe to Grow Here?
What the federal record shows across Maryland — and how to grow with it.
We checked the federal record across Maryland — 28,014 documented sites across 8 of the 9 source types we track.
The most significant on record: 167 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
Maryland carries one of the heavier federal records we track — and that's not a verdict on your yard. Proximity to a documented site is information, not a diagnosis: nothing here says any particular parcel is affected. It does earn one concrete step — before food beds go in the ground, a professional soil test tells you exactly what you're working with, and raised beds with clean imported soil grow well almost anywhere in the meantime.
Sources Checked
across Maryland
Severity Distribution
across Maryland
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Maryland, CAFO runs higher than the national average — 623 sites across Maryland. It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
CAFO: CAFOs pose a different contamination profile than chemical sources.
Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What Else to Consider for Pickerel Weed in Maryland
Zone compatibility tells you about winter cold survival — but Maryland growers also need to think about:
Heavy Piedmont clay drains poorly
Humidity and heat in summer promote disease
Deer pressure in suburban areas is extreme
Growing pickerel weed here specifically
Pickerel Weed needs pH 4.0–7.0; Maryland's dominant silt loam soils may or may not deliver that, so your parcel's SSURGO map unit is the real test.
Start with a soil test on your own ground and adjust pH and texture to fit pickerel weed's 4.0–7.0 range. How to handle it →
What to actually do about these — and the constraints that apply to every Maryland grower, not just pickerel weed — is covered on the Maryland growing guide.
Timing shifts within Maryland
Maryland isn't one climate. In Garrett County, the last hard freeze (28°F) holds until about Apr 22 — roughly 29 days later than the recorded state median — so plant pickerel weed to your county's window, not the statewide date.
Pickerel Weed needs about 90 days of frost-free season to complete its cycle. Even Garrett County — Maryland’s shortest season at 190 frost-free days — clears that by 100 days, so season length isn’t the constraint anywhere in Maryland. What varies is your own parcel.
Across Maryland’s 24 counties the frost-free season runs from 190 days in Garrett County to 270 days in Talbot County — a spread of 80 days, which is why a single statewide planting date misleads. The median Maryland county sees 238 frost-free days, leaving pickerel weed about 148 days of slack on a typical parcel — room for a second sowing where the season runs long.
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"). Pickerel Weed'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
Pickerel Weed draws native bees (low value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, pickerel weed can only work that bloom inside Maryland's frost window — roughly 238 days, opening after the last 28°F freeze (Mar 18 - Mar 29) and closing at the first (Nov 11 - Nov 27), per NOAA Regional Climate Centers ACIS, 1991-2020.
Recommended Pickerel Weed Varieties for Maryland
Maryland publishes no state variety trial for pickerel weed, so we won't invent a "best for Maryland" list. Choose types rated to your USDA hardiness zone (5b-8a), and confirm winter survival and drainage against your own parcel.
Maryland Cooperative Extension
For Maryland-specific cultivar recommendations, planting calendars, and pest pressure for pickerel weed, the canonical source is University of Maryland Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.
Is Pickerel Weed native to Maryland?
No — the USDA PLANTS Database lists Pickerel Weed as introduced rather than native in the Lower 48, so it is not part of Maryland's native flora. It grows here as a garden plant; pairing it with a few Maryland natives keeps local pollinators fed too.
Looking for plants that belong here? The Maryland 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 Pickerel Weed in Maryland
When can I plant Pickerel Weed in Maryland?
Maryland's last spring hard freeze (28°F) clears between Mar 18 and Mar 29, and the first fall hard freeze lands between Nov 11 and Nov 27 (NOAA Regional Climate Centers ACIS, 1991-2020). No sourced winter-hardiness floor is on record for Pickerel Weed, so this page does not state whether it overwinters in Maryland and publishes no fall establishment date for it — check its hardiness range against your own zone before treating it as a permanent planting.
What hardiness zone is Pickerel Weed grown in across Maryland?
Maryland spans USDA hardiness zones 5b-8a (USDA ARS PHZM 2023). Pickerel Weed carries a range of zones 10-12, so the overlap zones are where outdoor growing is most reliable.
How many frost-free days does a typical Maryland site have?
A typical Maryland site sees ~238 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Pickerel Weed 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 Garrett, the freeze-free season runs shorter than the state average, so verify your own county's window.
Is Pickerel Weed native to Maryland?
No — the USDA PLANTS Database lists Pickerel Weed as introduced rather than native in the Lower 48, so it is not part of Maryland's native flora. It grows here as a garden plant; pairing it with a few Maryland natives keeps local pollinators fed too.
How should I amend the soil for Pickerel Weed in Maryland?
Pickerel Weed tolerates pH 4-7 and poorly (saturated >50% of year) drainage (FAO ECOCROP). That is a 3-unit span, acid ground through alkaline, so pH is rarely what limits this plant on a Maryland site — amend for drainage and organic matter first.
Will Pickerel Weed actually grow on my specific land in Maryland?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores pickerel weed against your address's exact soil pH, drainage, sun, and frost-date data drawn from USDA SSURGO, NOAA, and PRISM — not state averages.
Check your specific parcel in Maryland
State-level data is a sketch. Your Growable Ground report scores pickerel weed against your parcel's exact soil, sun, drainage, and frost data — not zone averages.
Three things about your lot that Maryland pickerel weed averages can't show:
We read public map data around Maryland — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Maryland pickerel weed average
Explore More
Growing guides for pickerel weed
Explore Maryland county by county
Maryland carries 24 counties with their own USDA zone — a sample of the growing pages for pickerel weed there:
Where else pickerel weed grows
Pickerel Weed's zone band crosses state lines — these are the states closest to Maryland 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 Maryland
Maryland has a growing page for 1,020 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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