When to plant Swiss chard in Montana
In spring, from Apr 15 – June 15 in Billings to June 1 – 15 in Butte-Silver Bow (balance).
In fall, from May 15 – July 1 in Butte-Silver Bow (balance) to June 1 – July 5 in Missoula.
USDA's earliest safe spring and latest safe fall planting dates, matched to each place's average frost dates.
| Place | Spring | Fall |
|---|---|---|
| Belgrade | May 20 – June 1 | June 1 – July 1 |
| Billings | Apr 15 – June 15 | June 1 – July 20 |
| Bozeman | May 20 – June 1 | June 1 – July 1 |
| Butte-Silver Bow (balance) | June 1 – 15 | May 15 – July 1 |
| Great Falls | Apr 20 – June 15 | June 1 – July 5 |
| Helena | Apr 20 – June 15 | June 1 – July 5 |
| Kalispell | May 20 – June 1 | May 15 – July 1 |
| Missoula | Apr 20 – June 15 | June 1 – July 5 |
Planting dates: USDA Home and Garden Bulletin No. 9 (1967), tables 4 and 5. Frost dates: NOAA U.S. Climate Normals 1991–2020. “—” means the place's frost date is outside the table. The full USDA table for swiss chard.