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When to plant in Knightdale, NC

USDA Zone 8a

Here are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Knightdale, North Carolina — all computed from Knightdale's nearest NOAA weather station.

These dates come from a station roughly 17 km away, the closest with full normals; terrain around Knightdale (elevation, water, pavement) can move your real frost dates a few days either way. Zone 8a means many perennials and even some tender shrubs overwinter in Knightdale, while your frost dates still decide when annuals go out.

Station · CLAYTON WTP · 17.0 km
Last spring frost
April 7
50% chance · 32°F
First fall frost
November 3
50% chance · 32°F
Growing season
210 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for KnightdaleA year-band showing 32°F frost risk from January to December for Knightdale: last spring frost around April 7, first fall frost around November 3, about 210 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

CLAYTON WTP · 1991–2020

The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Knightdale’s own odds, recorded at CLAYTON WTP.

Frost-probability curves for KnightdaleProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around April 7 and the first fall frost around November 3, giving about 210 frost-free days.
Last spring frostFirst fall frostbold = 32°F · thin = 28°F / 36°F · dot = 50% date · band = 10–90% window
ThresholdSPRING 10%SPRING 50%SPRING 90%FALL 10%FALL 50%FALL 90%
36°FApr 30Apr 18Apr 3Oct 14Oct 26Nov 5
32°FApr 20Apr 7Mar 23Oct 22Nov 3Nov 16
28°FApr 12Mar 27Mar 7Nov 1Nov 14Dec 1

Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.

What to plant now

TODAY · JULY 19
Fall sowopen now
Brussels Sprouts
July 14July 28
Fall sowin 9 days
Rutabaga
July 28August 11
Fall sowin 23 days
Broccoli
August 11August 25
Fall sowin 23 days
Cabbage
August 11August 25
Fall sowin 23 days
Carrot
August 11August 25
Fall sowin 23 days
Cauliflower
August 11August 25
Fall sowin 23 days
Napa Cabbage
August 11September 8

Add these crops to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

Each bar is the exact window to take a planting action in Knightdale, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 18 km · complete 32°F normals

When stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.

CLAYTON WTP
Primary
17 km · 91 m elevation
SPRING
Apr 7
FALL
Nov 3
RALEIGH STATE UNIV
18 km · 122 m elevation
SPRING
Mar 28
FALL
Nov 8
RALEIGH 4 SW
18 km · 128 m elevation
SPRING
Mar 28
FALL
Nov 9

Knightdale planting FAQ

When is the last spring frost in Knightdale, NC?

Knightdale's average last spring frost falls near April 7 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.

When is the first fall frost in Knightdale, NC?

Expect Knightdale's first fall frost near November 3 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is Knightdale in?

Knightdale is in USDA hardiness zone 8a. In zone 8a, winters are mild — many tender perennials overwinter here.

How long is the growing season in Knightdale?

There are roughly 210 frost-free days in Knightdale (a moderate growing season), running from the average last frost around April 7 to the first fall frost near November 3.

When should I plant tomatoes in Knightdale?

In Knightdale, start tomato seeds indoors around February 10–February 24, then transplant seedlings outdoors around April 14 once the danger of frost has passed.

Planting reminders

Never miss a window in Knightdale

An email when it’s time to start seeds, transplant, and sow — timed to Knightdale’s frost dates. Double opt-in, one-click unsubscribe, no spam.

Nearby cities

8 within reach

Frost dates recorded at CLAYTON WTP, 17 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.

Cite this page
BlissGarden. "When to Plant in Knightdale, NC — Frost Dates & Zone 8a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00311820. Retrieved from https://blissgarden.com/north-carolina/knightdale.