Four Oclock is a perennial grown for its blooms, which open in summer and return year after year. It's hardy across USDA zones 9 through 11 and shrugs off deer. Its summer flowers are a moderate draw for moths and hummingbirds. It roots deep, which helps it reach moisture in a dry spell and open up tight soil as it establishes.
Four Oclock — the short answer
Four Oclock: grown in zones 9–11, full sun, pH 5.5–7.5.
- USDA zones
- 9–11
- Not verified — NC State Extension Gardener Plant Toolbox lists zones 9a–10b
- Soil pH
- 5.5–7.5
- We haven't confirmed this against a published source yet.
- Sun
- Full Sun
- We haven't confirmed this against a published source yet.
Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS and university Extension sources — each tile names its own row's source, because per-field provenance varies.
Score Four Oclock on your exact land.
Zone averages can't see the slope, soil, frost, and sun that decide whether four oclock actually takes — and those shift from one yard to the next. Enter your address and we'll score four oclock against your land's real conditions.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
No card required · your parcel report in seconds — read in full free for your first 14 days
What Four Oclock is
Four Oclock grows as a perennial and reaches around three feet at maturity. It blooms in summer. It's also deer-resistant.
Mature height and bloom period: We haven't confirmed this against a published source yet.
How to grow Four Oclock
Four Oclock grows in USDA zones 9 through 11. Four Oclock does best in full sun — at least 6 hours of direct sun a day — and soil from pH 5.5 to 7.5, on well-drained ground.
USDA Zones
9-11
Not verified — NC State Extension Gardener Plant Toolbox lists zones 9a–10b
Soil pH
5.5 - 7.5
We haven't confirmed this against a published source yet.
Sun
Full Sun
We haven't confirmed this against a published source yet.
Drainage
well (dry spells)
We haven't confirmed this against a published source yet.
Minimum Growing Temperature
41°F
Below this it stops growing rather than dies — a pace limit, not a survival limit.
We haven't confirmed this against a published source yet.
Mature Height
3 ft
We haven't confirmed this against a published source yet.
Start the season right
Plant four oclock in full sun with at least 6 hours of direct sun. It grows in the cool halves of the year, so sow it in spring or late summer rather than waiting for midsummer heat. We haven't confirmed this against a published source yet.
Match the soil
Four Oclock prefers pH 5.5 to 7.5. We haven't confirmed this against a published source yet. A quick soil test from your local Extension lab tells you whether to add lime or sulfur to land in band.
Water steadily
Keep the root zone evenly moist through establishment. We haven't confirmed this against a published source yet. A 2–3 inch mulch layer holds moisture without waterlogging.
Harvest at its peak
Cut four oclock blooms in the cool of the morning, just as they open, for the longest display.
Where Four Oclock thrives
Four Oclock is hardy across USDA zones 9 through 11. Zone is only the starting point, though: the soil pH, drainage, and frost dates on your specific land decide how well it actually does.
A USDA zone is a 10°F band of average annual extreme winter minimum, so zones 9–11 spans average winter lows from 20°F to 50°F (USDA PHZM 2023). Across the 50 states and DC, that band covers none outright but splits 17 down the middle — and which side of that line your land sits on changes the answer.
Zones 9–11·Where Four Oclock growsOpen map →
This map is derived from the USDA ARS / PRISM Plant Hardiness Zone Map (2023) and is not the official USDA Plant Hardiness Zone Map.
Where Four Oclock stands, state by state
Four Oclock is rated for zones 9–11 — a cold floor USDA puts at 20 to 30°F. Across the 50 states and DC, 0 sit fully inside that band, the line runs through 17 more, and 34 sit outside it — and inside every split state, the same line runs on at county grain.
The line runs through
17 states
- Alaska · zones 1a-9a
- California · zones 4b-11a
- Nevada · zones 4a-10a
3 of 17 shown
Four Oclock’s band covers part of each of these states — which side of the line your county sits on changes the answer, and each state page draws it.
State zone extents: USDA Plant Hardiness Zone Map (PHZM) 2023. A zone is a 10°F band of average annual extreme minimum temperature, so a state that splits the band contains the boundary — its own page draws the county line, and a parcel report resolves which side your land sits on.
What grows around Four Oclock
Growing guides for four oclock
Related plants in perennial flower
Good to know
One caution for pet owners — four oclock is toxic to dogs and cats (mild severity). Keep it out of reach, and call ASPCA Animal Poison Control at (888) 426-4435 in an emergency. We haven't confirmed this against a published source yet.
Four Oclock offers moderate value to bees and other pollinators. We haven't confirmed this against a published source yet.
Your land is one point inside Four Oclock's range
This page resolves to the species. Your state page draws the county line, and a report reads the parcel — the soil pH, drainage, sun, and frost dates on your exact ground, which no species average can see.
See if Four Oclock will thrive on your land
Zone averages are a start. Your soil pH, drainage, sun exposure, and frost dates shape whether four oclock actually takes. We score it against the mapped and modelled conditions at your address.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
How we know this about Four Oclock
The figures above are cited per row, not per site: the pH band names this plant’s own source column, the three temperature figures each carry their own, and days-to-maturity cites the publication that actually lists it. All of it comes from the Growable Ground Plant Database — a compilation over FAO ECOCROP, USDA PLANTS, and university Extension sources, published openly with per-field provenance.
Grounded inUSDA PLANTS Database
Frequently asked questions
Can I grow Four Oclock in my zone?
Four Oclock grows in USDA hardiness zones 9 through 11. Zone is one factor — soil pH, drainage, and frost dates on your specific parcel also shape whether it takes.
When should you plant Four Oclock?
Four Oclock is a cool-season crop, so it goes in during the cool halves of the year — early spring, and again in late summer for a fall planting — rather than at the height of summer heat. Your local frost dates set the exact window — a Growable Ground report reads them for your address.
How much sun does Four Oclock need?
Four Oclock needs full sun — a spot that catches at least 6 hours of direct summer sun a day. We haven't confirmed this against a published source yet. In more shade it still grows, but usually gives a smaller, later crop. The catch is that a yard rarely gets even light everywhere — a fence, the house, or one tall tree can quietly take those hours. A Growable Ground report reads the real sun-hours across your land, canopy and buildings included, so you can pick the brightest bed before you plant.
What soil does Four Oclock need?
Four Oclock prefers soil pH 5.5 to 7.5, on well-drained ground. We haven't confirmed this against a published source yet. Your report scores your parcel's mapped soil against that using USDA SSURGO data.
Does Four Oclock attract pollinators?
Yes — four oclock's flowers are a solid nectar source for moths and hummingbirds. We haven't confirmed this against a published source yet.
Is Four Oclock safe for pets?
Four Oclock is toxic to dogs and cats with mild severity. Keep it out of reach, and call ASPCA Animal Poison Control at (888) 426-4435 in an emergency. We haven't confirmed this against a published source yet.
Keep exploring Four Oclock
Four Oclock state by state
Every state four oclock's zone reaches — 8 link straight to that state's four oclock growing page; the rest open the state's full growing guide.