Yes — Strong Match
ajuga (zones 5-11) covers every zone Connecticut contains (6a-7b), so hardiness is not what limits it anywhere in the state.
Ajuga in Connecticut — the short answer
Ajuga in Connecticut: hardy in zones 5–11, part sun, against a state median of ~207 frost-free days.
- Plant zones
- 5-11
- 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
- Connecticut zones
- 6a-7b
- USDA PHZM 2023
- Frost window
- Mar 31 - Apr 11 – Oct 30 - Nov 3
- 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.
Your yard isn't the whole zone.
Connecticut spans zones 6a-7b, 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 ajuga 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
Connecticut is not one climate
Connecticut’s winter-low ladder runs across 9 counties, from zone 6 in Northwest Hills County to zone 7 in South Central Connecticut County. That is 10°F between the two counties’ average coldest night — the difference between ajuga overwintering in the ground and coming under cover.
The middle half of 9 counties runs 6.5–6.5 zones, with a median of 6.5 zones — a 1-zone span end to end.
Measured across 9 Connecticut 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 in Connecticut Fits Best
Even within Connecticut's zones 6a-7b, county microclimates differ enough to change what thrives. These counties carry the closest zone match for ajuga (USDA PHZM 2023):
Zone Comparison
Ajuga Needs
- USDA Zones: 5-11
- Sun: Part Sun
- Mature size: 6 in tall
- Drought tolerance: Medium
Connecticut Has
- USDA Zones: 6a-7b
- Last Hard Freeze (28°F): Mar 31 - Apr 11
- First Hard Freeze (28°F): Oct 30 - Nov 3
- Annual Rainfall: 44-52 inches
- Common Soils: Glacial till, Sandy loam, River valley silt
Plant Zone Range (zones 5-11)
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 Ajuga in Connecticut
The frost window
Across Connecticut, the last spring hard freeze (28°F) clears between Mar 31 and Apr 11, and the first fall hard freeze lands between Oct 30 and Nov 3 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 202-day window you can count on — up to 217 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
Connecticut runs as cold as USDA zone 6, and no sourced winter-hardiness floor is on record for ajuga, so this page does not state whether it overwinters here — and gives no fall establishment date on the strength of a guess. Whether ajuga is a permanent planting or a replant-every-spring crop for you turns on your own zone within Connecticut; check its hardiness range against that before treating it as long-lived ground.
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.
Soil + Drainage Fit
Ajuga likes near-neutral soil (pH 5.5-7.5). That's the common-ground band across Connecticut's glacial till and sandy loam — a soil test confirms it for your site. Drainage matters: this plant wants well (dry spells). If your Connecticut site is heavier clay or sits in a low spot, raised beds or amendment with compost solve it.
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. Connecticut soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.
What Else to Consider for Ajuga in Connecticut
Zone compatibility tells you about winter cold survival — but Connecticut growers also need to think about:
Rocky glacial soils require clearing and amendment
Short growing season in northern hills
Deer pressure is high in suburban areas
What to actually do about these — and the constraints that apply to every Connecticut grower, not just ajuga — is covered on the Connecticut growing guide.
Where in Connecticut Ajuga Is Zone-Hardy
Ajuga is rated for USDA zones 5–11. Every one of Connecticut’s 9 counties sits inside that band — from Northwest Hills County at zone 6a to South Central Connecticut County at zone 7a — so winter cold is not what decides this plant anywhere in the state. What is left to vary is your own parcel: slope, shelter and cold-air drainage routinely move a site half a zone either way from the county figure.
Across those 9 counties Connecticut’s winter-low ladder runs from zone 6a in Northwest Hills County to zone 7a in South Central Connecticut County — 1 USDA zone of spread, which is 10°F between the two counties’ average coldest night of the year. That is why a statewide hardiness answer is where you start and not where you finish.
The planting window moves with it. Northwest Hills County holds its last hard freeze (28°F) until about Apr 19, while Greater Bridgeport County is clear by Mar 27 — 23 days apart. Set ajuga out on your county’s date, not the state’s.
County hardiness zones: USDA Plant Hardiness Zone Map (PHZM) 2023, per county. County last-freeze dates: NOAA Regional Climate Centers ACIS (1991-2020), county 28°F killing freeze — earlier than the folk 32°F "last frost". Ajuga’s zone 5–11 band: USDA PLANTS / Growable Ground plant database. A parcel report resolves your address’s own zone and frost dates rather than its county’s.
Pollinator + Wildlife Value
Ajuga draws honeybees and native bees (moderate value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, ajuga can only work that bloom inside Connecticut's frost window — roughly 207 days, opening after the last 28°F freeze (Mar 31 - Apr 11) and closing at the first (Oct 30 - Nov 3), per NOAA Regional Climate Centers ACIS, 1991-2020.
Connecticut Cooperative Extension
For Connecticut-specific cultivar recommendations, planting calendars, and pest pressure for ajuga, the canonical source is UConn Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.
Is Ajuga native to Connecticut?
No — the USDA PLANTS Database lists Ajuga as introduced rather than native in the Lower 48, so it is not part of Connecticut's native flora. It grows here as a garden plant; pairing it with a few Connecticut natives keeps local pollinators fed too.
Looking for plants that belong here? The Connecticut 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 Ajuga in Connecticut
When can I plant Ajuga in Connecticut?
Connecticut's last spring hard freeze (28°F) clears between Mar 31 and Apr 11, and the first fall hard freeze lands between Oct 30 and Nov 3 (NOAA Regional Climate Centers ACIS, 1991-2020). No sourced winter-hardiness floor is on record for Ajuga, so this page does not state whether it overwinters in Connecticut 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 Ajuga grown in across Connecticut?
Connecticut spans USDA hardiness zones 6a-7b (USDA ARS PHZM 2023). Ajuga carries a range of zones 5-11, so the overlap zones are where outdoor growing is most reliable.
How many frost-free days does a typical Connecticut site have?
A typical Connecticut site sees ~207 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Ajuga should be matched against that window, so check whether your local microclimate runs above or below the state average before settling on a planting date.
Is Ajuga native to Connecticut?
No — the USDA PLANTS Database lists Ajuga as introduced rather than native in the Lower 48, so it is not part of Connecticut's native flora. It grows here as a garden plant; pairing it with a few Connecticut natives keeps local pollinators fed too.
How should I amend the soil for Ajuga in Connecticut?
Ajuga prefers pH 5.5-7.5 and well (dry spells) drainage (USDA PLANTS). That sits in the common-ground band across Connecticut soils — a 30-minute soil test from a local Extension lab confirms it for your specific site.
Will Ajuga actually grow on my specific land in Connecticut?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores ajuga 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 Connecticut
State-level data is a sketch. Your Growable Ground report scores ajuga against your parcel's exact soil, sun, drainage, and frost data — not zone averages.
Three things about your lot that Connecticut ajuga averages can't show:
We read public map data around Connecticut — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Connecticut ajuga average
Explore More
Growing guides for ajuga
Last updated: