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Climate Info and Frost Dates
Zone/Region Info
Average Frost Dates
Autumn frost freeze dates
https://www.weather.gov/cae/Autumnfrostfreeze.html
| Minimum temperature of 36 degrees |
| | Columbia |
| Average Date | October 25 |
| Earliest Date | 10/3/1974 |
| Latest Date | 11/14/2003 |
| Minimum temperature of 32 degrees |
| | Columbia |
| Average Date | November 3 |
| Earliest Date | 10/4/1974 |
| Latest Date | 12/10/1978 |
| Minimum temperature of 28 degrees |
| | Columbia |
| Average Date | November 16 |
| Earliest Date | 10/22/1952 & 1974 |
| Latest Date | 12/19/2011 |
How to calculate indoor seed starting dates
Find your spring frost free date, then count back the number of weeks recommended on seed packets for indoor seed starting.
For example, Peppers can take 6-8 weeks to be ready for placing outside. Find your spring frost free date and count backwards 6-8 weeks.
From that you can figure out when to start the seeds of plants that transplant well seeds indoors:
| Crop | Weeks before last frost date | Indoor Start Date | Transplant Date |
| Broccoli | 7-9 | Feb 2 to Feb 9 | Mar 1 to Apr 10 |
| Pepper (1) | 8 | Feb 2 to Feb 9 | Apr 1 to May 15 |
| Tomato (1) | 6 | Mar 1 to Apr 30 | Mar 25 to Apr 30 |
There are also calculators online like:
Vegetables
| Crop | | Planting Date Range | Planting Date Range |
| | | Spring | Fall |
| Asparagus | | Feb 1 to Mar 15 | Not recommended |
| Beans, Snap | | Apr 1 to Jun 1 | Aug 1 to Sept 1 |
| Beans, Pole | | Apr 1 to Jun 1 | Aug 1 to Sept 1 |
| Beans, Half-Runner | | Apr 1 to Jun 1 | Aug 1 to Sept 1 |
| Beans, Lima | | Apr 15 to Jun1 | Jul 15 to Aug 1 |
| Beans, Pole Lima | | Apr 15 to Jun1 | Jul 15 to Aug 1 |
| Beans, Edible Soy | | Apr 15 to Jun1 | Jul 15 to Aug 1 |
| Beets | | Feb 15 to Mar 31 | Aug 15 to Sept 30 |
| Bok Choy | | | |
| Broccoli | | Mar 1 to Apr 10 | Sept 1 to Sept 30 |
| Brussels Sprouts | | Not recommended | Sept 15 to Oct 15 |
| Cabbage (1) | | Feb 1 to Mar 31 | Aug 15 to Sept 30 |
| Cantaloupe | | Mar 15 to May 15 | Jul 1 to Jul 30 |
| Carrots | | Feb 1 to Mar 15 | Sept 1 to Sept 15 |
| Cauliflower (1) | | Mar 1 to Apr 10 | Aug 15 to Aug 30 |
| Collards | | Feb 1 to Jun 15 | Aug 1 to Oct 30 |
| Cucumber | | Mar 15 to May 15 | Aug 1 to Aug 30 |
| Eggplant (1) | | Apr 1 to Apr 30 | Aug 1 to Aug 31 |
| Garlic | | Not recommended | Oct 1 to Nov 30 |
| Honeydew | | Mar 15 to May 15 | Jul 1 to Jul 30 |
| Kale | | Feb 1 to Jun 15 | Aug 1 to Oct 30 |
| Leeks | | Feb 1 to Jun 15 | Not recommended |
| Lettuce (2) | | Feb 1 to Apr 15 | Sept 5 to Nov 1 |
| Mustard (2) | | Feb 1 to Jun 15 | Aug 1 to Oct 15 |
| Onion, sets | | Feb 1 to Mar 15 | Sept 15 to Nov 15 |
| Onion, plants | | Not recommended | Oct 1 to Nov 15 |
| Onion, seeds | | Not recommended | Sept 15 to Oct 30 |
| Okra | | May 1 to Jun 30 | Not recommended |
| Peanuts | | Apr 1 to May 31 | Not recommended |
| Peas, Garden | | Feb 1 to Mar 15 | Aug 15 to Nov 30 |
| Peas, Southern | | Apr 1 to Jun 15 | July 15 to Aug 1 |
| Pepper (1) | | Apr 1 to May 15 | July 10 to Aug 10 |
| Potatoes, Irish | | Feb 1 to Mar 31 | Not recommended |
| Potatoes, Sweet | | Apr 15 to Jun 15 | Not recommended |
| Pumpkins | | Not recommended | Jun 1 -to Jun 30 |
| Radish (2) | | Feb 1 to Jun 15 | Aug 1 to Sept 30 |
| Rutabaga | | Feb 1 to Mar 31 | Aug 15 to Oct 15 |
| Spinach (2) | | Feb 1 to Apr 1 | Aug 15 to Oct 15 |
| Sweet Corn (2) | | Mar 1 to Apr 15 | Not recommended |
| Squash, Summer | | Mar 15 to Jul 31 | Aug 1 to Aug 31 |
| Squash, Winter | | Mar 20 to May 1 | Aug 1 to Aug 31 |
| Tomato (1) | | Mar 1 to Apr 30 | July 1 to Jul 31 |
| Turnips (2) | | Feb 1 to Apr 1 | Aug 1 to Sept 30 |
| Watermelon (1) | | Apr 1 to Apr 30 | Not recommended |
| (1) From Transplants |
| (2) Sequentially plant to extend the cropping season |
| Source: https://hgic.clemson.edu/factsheet/planning-a-garden/ |
Planting Charts
| Vegetable | Seed (100-foot row) | Spacing Between-row x In-row(inches) | Planting Depth | Aprox. Days to Harvest |
| Asparagus | — | 36 x 18 | 4 crowns | |
| Beans, Snap | ¾ pound | 36 x 2 | 1 | 50-60 |
| Beans, Pole | ½ pound | 36 x 4 | 1 | 60-70 |
| Beans, Half Runner | ½ pound | 36 x 2 | 1 | 55-65 |
| Beans, Lima | ¾ pound | 36 x 3 | 1½ | 65-75 |
| Beans, Pole Lima | ½ pound | 36 x 6 | 1½ | 70-75 |
| Beans, Edible Soy | ½ pound | 36 x 3 | 1 | 60-70 |
| Beets | ½ ounce | 30 x 2 | ¾ | 50-60 |
| Broccoli | ½ ounce | 36 x 18 | ½ | 60-70 |
| Brussels Sprouts | ½ ounce | 36 x 18 | ½ | 90-100 |
| Cabbage* | ½ ounce | 36 x 12 | 3 | 60-80 |
| Cantaloupe | 1 ounce | 60 x 24 | 1 | 75-85 |
| Carrots | ¼ ounce | 30 x 1¼ | ¼ | 60-70 |
| Cauliflower | ¼ ounce | 36 x 18 | ½ | 60-70 |
| Collards | ½ ounce | 36 x 8 | ½ | 60-70 |
| Cucumbers | 1 ounce | 60 x 12 | 1 | 50-60 |
| Eggplant* | — | 36 x 18 | 3 | 70-80 |
| Kale | ½ ounce | 36 x 1 | ½ | 50-55 |
| Lettuce, Leaf | ¼ ounce | 30 x 2 | ½ | 40-70 |
| Lettuce, Head | ⅛ ounce | 30 x 12 | ¼ | 30-50 |
| Lettuce, Mustard | ½ ounce | 30 x 2 | ½ | 40-60 |
| Onions, Green | 1 quart | 30 x 2 | 1½ sets | 35-45 |
| Onions, Bulb | ½ ounce | 30 x 3 | ½ seed | 100-120 |
| Okra | 1 ounce | 36 x 9 | ¾ | 60-70 |
| Peanuts | ¼ pound | 30 x 4 | 1½ | 100-120 |
| Peas, Garden | 1 pound | 36 x 1 | 1½ | 65-80 |
| Peas, Southern | ½ pound | 46 x 4 | 1½ | 75-85 |
| Pepper* | — | 36 x 18 | 3 | 60-70 |
| Potatoes, Irish | 12 pounds | 36 x 12 | 3 | 90-110 |
| Potatoes, Sweet* | — | 36 x 8 | 3 | 120 |
| Radish | ½ ounce | 24 x 1 | ½ | 25-30 |
| Rutabaga | ½ ounce | 36 x 12 | ¾ | 100-110 |
| Spinach | 1 ounce | 30 x 2 | ½ | 50-60 |
| Sweet Corn | 4 ounce | 36 x 10 | 1 | 80-95 |
| Squash, Summer | 1 ounce | 36 x 15 | 1 | 50-60 |
| Squash, Winter | ½ ounce | 60 x 48 | 1½ | 90-120 |
| Tomato* | — | 60 x 24 | 4 | 70-80 |
| Turnips | ¼ ounce | 30 x 2 | ½ | 60-70 |
| Watermelon | ½ ounce | 60 x 60 | 1½ | 80-100 |
| *Transplants |
| Source: https://hgic.clemson.edu/factsheet/planning-a-garden/ |
Planting Dates
| Basil | Seeds sown indoors 4-6 week ahead of out door planting time. Transplant outdoors when daytime temperature is consistently in the 70s and nighttime temperatures are above 50°F. | Clemson HGIC - Herbs |
| Parsley | Start seeds indoors six weeks before average date of last frost. Transplant outdoors two to three weeks before average date of last frost. | Clemson HGIC - Herbs |
| Cilantro | This cool-season herb may be planted in fall or early spring. It prefers temperatures between 50°F and 85°F. It will bolt when temperatures exceed 85°F. | Clemson HGIC - Herbs |
Planting Dates
| Sunflower | Start indoors 3–4 weeks before last frost at temperatures of 65–75°F or direct sow after frost. | |
| Blanket flower (Gaillardia aristata) | Start seeds early indoors 4-6 weeks before the last spring frost, transplanting to the garden when the weather has warmed. In warm-winter areas, sow seeds directly in late fall or very early spring. | |
| Black-eyed susan (Rudbeckia hirta) | Plant black-eyed Susans when the soil temperature has reached 70°F for best seed germination. In many parts of North America, the planting period is March to May. Germination takes 7 to 30 days. | Clemson HGIC - Rudbeckia |
| Coneflower (Echinacea purpurea) | Sow seed indoors in an area with an air temperature of 65 to 70 °F. Cover seeds lightly with potting soil to prevent light from inhibiting germination. Keep the seed bed misted until germination occurs 10 to 20 days later. Seedlings should be ready to transplant 20 to 28 days after sowing. Seeds can also be started outdoors in the spring or summer, up to 2 months before frost. | Clemson HGIC - Echinacea |
| Scarlet sage (Salvia coccinea) | Start seed indoors 6-8 weeks before the average last frost. Sow seeds shallowly, as they require light to germinate. It takes 2-3 weeks for the seeds to germinate. Transplant outdoors. | Clemson HGIC - Salvia |
| Zinnia | Zinnias are sensitive to frost, so do not seed until the last frost has passed. Zinnias will grow in a minimum daytime temperature of about 60°F, though a range of 74–84°F is preferred. | |