Frost Dates & Planting Calendar for Port Royal, SC
Plan your garden around Port Royal, SC's typical frost-free growing season, using NOAA climate normals and a 42-crop planting calendar built for this location.
Last Spring Frost
March 3
Safe Mar 20
Typical Mar 3
Risky Feb 2
First Fall Frost
December 9
Safe Nov 21
Typical Dec 9
Risky Jan 4
Growing Season
282 days
Typical last frost to typical first frost.
USDA Hardiness Zone
Zone 9a
Subtropical to frost-free — heat, not cold, is the main limit on what you can grow.
Data: NOAA station BEAUFORT WWTP, SC US, 1.8 km away.
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days until the typical last spring frost
Monthly Temperatures
Avg. high
Avg. temp
Avg. low
Planting Calendar
| Crop | Start indoors | Direct sow | Transplant | Fall planting | Maturity | Notes |
|---|---|---|---|---|---|---|
| Tomato | Jan 6 – Jan 20 | — | Mar 10 – Mar 17 | — | 60–85 days | Start indoors 6-8 weeks before last frost; transplant out 1-2 weeks after last frost once soil has warmed. |
| Pepper | Dec 23 – Jan 6 | — | Mar 10 – Mar 24 | — | 60–90 days | Slow to germinate; start indoors 8-10 weeks before last frost. Transplant only once nights stay above 55F, 1-3 weeks after last frost. |
| Eggplant | Dec 23 – Jan 6 | — | Mar 17 – Mar 24 | — | 65–85 days | Warm-season crop, similar timing to pepper; needs consistently warm soil (65F+) to transplant. |
| Cucumber | Feb 3 – Feb 10 | Mar 10 – Mar 17 | Mar 10 – Mar 17 | — | 50–65 days | Can be started indoors 3-4 weeks before transplanting, or direct-sown 1-2 weeks after last frost once soil is warm. |
| Zucchini | Feb 10 – Feb 17 | Mar 10 – Mar 24 | Mar 10 – Mar 17 | — | 45–55 days | Fast-growing squash; direct sow 1-3 weeks after last frost, or start indoors 2-3 weeks early for a head start. |
| Winter Squash | Feb 3 – Feb 10 | Mar 10 – Mar 24 | Mar 10 – Mar 17 | — | 80–110 days | Long season; direct sow after soil warms, or start indoors 3-4 weeks before last frost in short-season climates. |
| Pumpkin | — | Mar 10 – Mar 24 | — | — | 90–120 days | Direct sow 1-3 weeks after last frost; back-time from your first fall frost so the 90-120 day maturity window lands before it. |
| Watermelon | Feb 3 – Feb 10 | — | Mar 17 – Mar 24 | — | 70–90 days | Needs warm soil (65F+); start indoors 3-4 weeks before last frost, transplant 2-3 weeks after last frost. |
| Cantaloupe | Feb 3 – Feb 10 | — | Mar 17 – Mar 24 | — | 70–90 days | Same warm-soil requirements as watermelon; avoid disturbing roots when transplanting. |
| Corn | — | Mar 3 – Mar 17 | — | — | 60–100 days | Direct sow at last frost to 2 weeks after, once soil reaches 60F; does not transplant well. Succession sow every 2 weeks. |
| Green Bean | — | Mar 3 – Mar 17 | — | — | 50–65 days | Direct sow at last frost to 2 weeks after, once soil has warmed; frost-tender, do not rush. |
| Pea | — | Jan 20 – Feb 3 | — | — | 55–70 days | Cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Lettuce | — | Feb 3 – Feb 17 | — | Oct 14 – Oct 28 | 45–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. Also transplantable from indoor starts. |
| Spinach | — | Jan 20 – Feb 3 | — | Oct 14 – Oct 28 | 40–50 days | Very cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Kale | — | Feb 3 – Feb 17 | — | Sep 30 – Oct 14 | 50–65 days | Cold-hardy; direct sow 2-4 weeks before last frost or start indoors for earlier transplants. |
| Arugula | — | Feb 3 – Feb 17 | — | Oct 28 – Nov 4 | 30–40 days | Fast-growing, cold-tolerant green; direct sow 2-4 weeks before last frost, succession sow every 2-3 weeks. |
| Swiss Chard | — | Feb 10 – Feb 24 | — | — | 50–60 days | Fairly cold-hardy; direct sow 1-3 weeks before last frost. Tolerates light frost in fall too. |
| Broccoli | Jan 13 – Jan 27 | — | Feb 10 – Feb 17 | Oct 7 – Oct 14 | 55–80 days | Start indoors 5-7 weeks before last frost; transplant out 2-3 weeks before last frost (hardens off to light frost). |
| Cauliflower | Jan 13 – Jan 27 | — | Feb 17 – Feb 24 | Sep 30 – Oct 7 | 55–85 days | Fussier than broccoli about temperature swings; start indoors 5-7 weeks before last frost, transplant 1-2 weeks before last frost. |
| Cabbage | Jan 13 – Jan 27 | — | Feb 3 – Feb 17 | Sep 30 – Oct 14 | 60–100 days | Cold-hardy; start indoors 5-7 weeks before last frost, transplant 2-4 weeks before last frost. |
| Brussels Sprouts | Jan 13 – Jan 27 | — | Feb 10 – Feb 24 | — | 90–110 days | Long-season crop best timed to mature after a light fall frost for sweetest flavor; start indoors 5-7 weeks before last frost. |
| Carrot | — | Feb 3 – Feb 17 | — | Sep 16 – Sep 30 | 60–80 days | Direct sow only (does not transplant); sow 2-4 weeks before last frost, as soon as soil can be worked. |
| Beet | — | Feb 3 – Feb 17 | — | Sep 30 – Oct 14 | 50–65 days | Direct sow 2-4 weeks before last frost; tolerates light frost. |
| Radish | — | Jan 27 – Feb 10 | — | Oct 28 – Nov 11 | 22–30 days | Very fast and cold-hardy; direct sow 3-5 weeks before last frost, as soon as soil can be worked. |
| Turnip | — | Feb 3 – Feb 17 | — | Sep 30 – Oct 14 | 40–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. |
| Onion | Dec 23 – Jan 6 | — | Feb 3 – Feb 17 | — | 90–120 days | Start seeds indoors 8-10 weeks before last frost (or use sets/transplants); set out 2-4 weeks before last frost, very cold-tolerant as seedlings. |
| Garlic | — | — | — | Nov 11 – Nov 25 | 240–270 days | Fall-planted crop only; not planted in spring in most climates. |
| Potato | — | Feb 3 – Feb 17 | — | — | 70–120 days | Plant seed potatoes 2-4 weeks before last frost, as soon as soil can be worked and is above 45F; light frost on emerging foliage is usually tolerated. |
| Sweet Potato | — | — | Mar 17 – Mar 31 | — | 90–120 days | Set out slips 2-4 weeks after last frost once soil is thoroughly warm (65F+); very frost/cold sensitive. |
| Asparagus | — | — | Feb 3 – Feb 17 | — | 730–1095 days | Perennial; plant crowns 2-4 weeks before last frost as soon as soil can be worked. Takes 2-3 years to full production. |
| Crop | Start indoors | Direct sow | Transplant | Fall planting | Maturity | Notes |
|---|---|---|---|---|---|---|
| Basil | Jan 20 – Jan 27 | — | Mar 10 – Mar 17 | — | 50–70 days | Very frost/cold sensitive; start indoors 5-6 weeks before last frost, transplant only after all danger of frost (1-2 weeks after) and nights stay warm. |
| Cilantro | — | Feb 10 – Feb 24 | — | Oct 14 – Oct 28 | 45–70 days | Cool-season, bolts in heat; direct sow 1-3 weeks before last frost, succession sow through spring. |
| Parsley | Jan 6 – Jan 20 | — | Feb 17 – Feb 24 | — | 70–90 days | Slow to germinate; start indoors 6-8 weeks before last frost, transplant 1-2 weeks before last frost (biennial, cold-tolerant). |
| Dill | — | Feb 10 – Feb 24 | — | — | 40–60 days | Taprooted, does not transplant well; direct sow 1-3 weeks before last frost, succession sow through summer. |
| Oregano | Jan 6 – Jan 20 | — | Mar 3 – Mar 10 | — | 80–90 days | Perennial herb; start indoors 6-8 weeks before last frost, transplant around/just after last frost date. |
| Thyme | Jan 6 – Jan 20 | — | Mar 3 – Mar 10 | — | 85–95 days | Perennial herb, slow from seed; start indoors 6-8 weeks before last frost, transplant around/after last frost. |
| Crop | Start indoors | Direct sow | Transplant | Fall planting | Maturity | Notes |
|---|---|---|---|---|---|---|
| Sunflower | — | Mar 10 – Mar 24 | — | — | 70–100 days | Direct sow 1-3 weeks after last frost once soil has warmed; taprooted, resents transplanting. |
| Zinnia | Feb 3 – Feb 10 | Mar 10 – Mar 24 | Mar 10 – Mar 17 | — | 60–70 days | Frost-tender; direct sow 1-3 weeks after last frost, or start indoors 3-4 weeks early for earlier blooms. |
| Marigold | Jan 20 – Feb 3 | — | Mar 10 – Mar 17 | — | 45–60 days | Frost-tender; start indoors 4-6 weeks before last frost, transplant after all frost danger has passed. |
| Cosmos | Feb 3 – Feb 10 | Mar 10 – Mar 24 | Mar 10 – Mar 17 | — | 60–90 days | Easy from direct seed 1-3 weeks after last frost; can also start indoors 3-4 weeks early. |
| Nasturtium | — | Mar 10 – Mar 24 | — | — | 50–65 days | Frost-tender, resents root disturbance; direct sow 1-3 weeks after last frost once soil has warmed. |
| Dahlia | — | — | Mar 10 – Mar 24 | — | 90–120 days | Plant tubers 1-3 weeks after last frost once soil is warm (60F+); very frost-sensitive. |
Date ranges are estimates based on university extension guidelines and this city's NOAA frost normals — not a guarantee. Scroll to see all columns on narrow screens.
Frequently Asked Questions
When is the last frost in Port Royal, SC?
Based on 1991–2020 NOAA climate normals for the BEAUFORT WWTP, SC US station, the last spring frost in Port Royal typically falls around March 3. A cautious gardener might wait until March 20 (only a 10% chance of a later frost), while February 2 marks an earlier, higher-risk planting date.
When is the first frost in Port Royal, SC in fall?
The first fall frost in Port Royal typically arrives around December 9. To stay safe, assume frost could start as early as November 21; in milder years it can hold off until January 4.
How long is the growing season in Port Royal, SC?
Port Royal's average frost-free growing season is about 282 days, running from the typical last spring frost (March 3) to the typical first fall frost (December 9).
What USDA hardiness zone is Port Royal, SC in?
Port Royal, SC is in USDA plant hardiness zone 9a, per the USDA's 2023 Plant Hardiness Zone Map. Subtropical to frost-free — heat, not cold, is the main limit on what you can grow.