Frost Dates for Denver, PA 17517
Last spring frost April 27 · First fall frost October 15 · 171 frost-free days · USDA Zone 7a
Frost probability for 17517
| Frost | 10% | 50% | 90% |
|---|---|---|---|
| Spring (last frost) | May 10 | April 27 | April 13 |
| Fall (first frost) | October 1 | October 15 | October 28 |
Dates come from NOAA 1971–2000 freeze probabilities at the nearest reporting station (30.1 km away); the 50% date is the median year.
Month by month in Denver
| Month | What to do |
|---|---|
| January | Plan your garden layout and order seeds. Research varieties suited to your frost dates. |
| February | Start peppers and eggplant indoors 8–10 weeks before your last frost (around April 27). Start tomatoes about two weeks later, 6–8 weeks before last frost. |
| March | Start herbs, basil, and squash indoors (4–6 weeks before frost). Direct sow peas, spinach, and lettuce if soil is workable. |
| April | Last frost around April 27. Transplant cold-hardy crops (broccoli, kale, cabbage). Harden off tomato and pepper seedlings. |
| May | Frost has passed. Transplant tomatoes, peppers, and basil outdoors. Direct sow beans, cucumbers, squash, and zucchini. |
| June | Succession plant lettuce and greens. Keep beds weeded and watered consistently. |
| July | Harvest regularly to encourage production. Monitor for pests and disease. |
| August | Midsummer: harvest beans, zucchini, cucumbers. Start brassica seeds indoors for fall. |
| September | First fall frost approaching (around October 15). Transplant fall brassicas. Sow spinach, arugula, and radishes. |
| October | First frost around October 15. Harvest tomatoes and peppers before frost. Cover cold-hardy crops with row covers to extend the season. |
| November | Harvest remaining cold-hardy crops: kale, carrots, and beets. Plant garlic bulbs for next year. |
| December | Clean up spent plants. Add compost to beds. Rest, review, and plan next year's garden. |
What grows in a 171-day season
Frequently Asked Questions
What is the last frost date for Denver, PA (ZIP 17517)?
The median last spring frost date for Denver, PA (ZIP code 17517) is around April 27. This is the 50th-percentile date — meaning half of all years see frost end before this date. Use the 10% and 90% dates to understand the full range of risk in your area.
What is the first fall frost date in Denver, PA?
The median first fall frost date for Denver, PA is around October 15. Plan to harvest or protect frost-sensitive crops like tomatoes and peppers at least a week before this date to avoid losses.
How long is the growing season in Denver, PA?
The frost-free growing season in Denver is about 171 days. This window — from your last spring frost to your first fall frost — is when warm-season vegetables thrive. Cold-hardy crops like kale, spinach, and peas can extend your season by weeks on either side.
What USDA hardiness zone is Denver, PA?
Based on frost date patterns, Denver falls approximately in 7a. USDA hardiness zones are determined by average annual minimum winter temperatures and guide both plant selection and planting timing for your location.
When should I start tomatoes indoors in Denver, PA?
Start tomato seeds indoors 6–8 weeks before your last frost date (around April 27). For Denver, that's roughly March 2 to March 16. Transplant outdoors 1–2 weeks after your last frost.
Nearby and related
- Frost dates for Ephrata, PA 17522 (5.2 mi)
- Frost dates for Mohnton, PA 19540 (8.7 mi)
- Frost dates for Lititz, PA 17543 (9.9 mi)
- Frost dates for New Holland, PA 17557 (10.2 mi)
- Frost dates for Leola, PA 17540 (10.5 mi)
- When to plant in PA
- When to plant Peppers in PA
- When to plant Cucumbers in PA
- When to plant Zucchini in PA
- When to plant Butternut Squash in PA
- When to plant Basil in PA
- When to plant Sweet Corn in PA
- Look up another ZIP