When to plant in Round Rock, TX
USDA Zone 9aEverything below — frost dates, hardiness zone, and what to plant when in Round Rock, Texas — is derived from the closest NOAA station with complete climate normals.
A generous ~254-day season lets Round Rock gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. These dates come from a station roughly 16 km away, the closest with full normals; terrain around Round Rock (elevation, water, pavement) can move your real frost dates a few days either way. In zone 9a, frost is a minor factor for Round Rock — most perennials thrive, and annual vegetables can go out early and stay late.
Frost probability
AUSTIN GREAT HILLS · 1991–2020The 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 Round Rock’s own odds, recorded at AUSTIN GREAT HILLS.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | Apr 11 | Mar 25 | Mar 6 | Oct 27 | Nov 10 | Nov 27 |
| 32°F | Mar 29 | Mar 11 | Feb 22 | Nov 3 | Nov 20 | Dec 9 |
| 28°F | Mar 19 | Mar 1 | Jan 31 | Nov 12 | Dec 3 | Dec 29 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Round Rock, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 25 km · complete 32°F normalsWhen 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.
Round Rock planting FAQ
When is the last spring frost in Round Rock, TX?
Round Rock's average last spring frost falls near March 11 — 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 Round Rock, TX?
The first fall frost in Round Rock typically arrives around November 20 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Round Rock in?
Round Rock is in USDA hardiness zone 9a. In zone 9a, winters are mild — many tender perennials overwinter here.
How long is the growing season in Round Rock?
Round Rock has about 254 frost-free days — a long growing season — between the average last spring frost (March 11) and first fall frost (November 20).
When should I plant tomatoes in Round Rock?
For Round Rock, sow tomatoes indoors about January 14–January 28 and move the seedlings out around March 18, after the last spring frost.
Never miss a window in Round Rock
An email when it’s time to start seeds, transplant, and sow — timed to Round Rock’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Brushy Creek · 7 km
- Wells Branch · 9 km
- Pflugerville · 11 km
- Hutto · 12 km
- Cedar Park · 15 km
- Georgetown · 16 km
- Leander · 20 km
- Manor · 22 km
Frost dates recorded at AUSTIN GREAT HILLS, 16 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Round Rock, TX — Frost Dates & Zone 9a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00410433. Retrieved from https://blissgarden.com/texas/round-rock.