When to plant in Griffith, IN
USDA Zone 6aGriffith, Indiana frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.
Heads up: the nearest complete-normals station is about 22 km from Griffith, so your yard's frost dates can differ — a low spot or a paved city center can shift them by a week. In zone 6a, Griffith gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
Frost probability
PARK FOREST · 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 Griffith’s own odds, recorded at PARK FOREST.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 24 | May 5 | Apr 20 | Sep 27 | Oct 10 | Oct 22 |
| 32°F | May 11 | Apr 23 | Apr 9 | Oct 6 | Oct 20 | Nov 1 |
| 28°F | Apr 27 | Apr 12 | Mar 30 | Oct 18 | Oct 30 | Nov 15 |
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 Griffith, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 30 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.
Griffith planting FAQ
When is the last spring frost in Griffith, IN?
On average, the last spring frost in Griffith is around April 23 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.
When is the first fall frost in Griffith, IN?
Expect Griffith's first fall frost near October 20 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.
What hardiness zone is Griffith in?
Griffith is in USDA hardiness zone 6a. In zone 6a, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Griffith?
Griffith has about 180 frost-free days — a moderate growing season — between the average last spring frost (April 23) and first fall frost (October 20).
When should I plant tomatoes in Griffith?
For Griffith, sow tomatoes indoors about February 26–March 12 and move the seedlings out around April 30, after the last spring frost.
Never miss a window in Griffith
An email when it’s time to start seeds, transplant, and sow — timed to Griffith’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Highland · 4 km
- Schererville · 5 km
- Munster · 7 km
- Dyer · 8 km
- Gary · 9 km
- St. John · 10 km
- Merrillville · 11 km
- Lansing · 11 km
Frost dates recorded at PARK FOREST, 22 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 Griffith, IN — Frost Dates & Zone 6a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00116616. Retrieved from https://blissgarden.com/indiana/griffith.