Regional guide

South Dakota Frost and Soil Temperature Vegetable Garden

An SDSU Extension guide for South Dakota vegetable timing, frost-free windows, soil-temperature groups, fall succession dates, and crop-row spacing.

Climate signals

• SDSU Extension Vegetable Gardening in South Dakota, P-00123, lists a Revision Date: March 2026.
• The guide says to use the maps on the back cover to determine the average date of the last spring frost and first fall frost for your location.
• It also says personal experience and experienced gardeners' advice help, particularly in areas where there are wide variations in elevation.
• As an example, most of the southeast part of South Dakota is frost-free between May 1 and September 24, for a total of 147 frost-free growing days.
• The source says cool season crops can be planted earlier, while warm season crops will be injured if planted too early.

Planning notes

• Table 1 says warm season crops do not grow well in cool weather under 50 F and are damaged by frost; their optimum soil temperature is 60 to 75 F.
• Warm-season soil-temperature groups put lima beans, sweet corn, squash, pumpkins, and snap beans at a 50 F minimum; cucumbers and muskmelons at 60 F; and tomatoes, eggplant, pepper, and watermelons at 65 F.
• Table 4 gives crop-row examples with row spacing, plant spacing, depth, weeks to transplant size, time of planting or transplanting outdoors, days to germinate, days to harvest, suggested amount, frost hardy status, and harvest cues.
• Beans, Snap use May-July outdoor timing, 1 inch depth, 6-10 germination days, 60-65 days to harvest for pole beans, 50-60 days for bush beans, and are not frost hardy.
• Beets use April-July outdoor timing, 1/2 inch depth, 7-12 germination days, 50-65 days to harvest, and Semi frost hardiness.
• Carrots use April-June outdoor timing, 1/4 inch depth, 7-14 germination days, 55-80 days to harvest, and Semi frost hardiness.
• Corn, Sweet uses May-early July outdoor timing, 1/2-1 inch depth, 5-12 germination days, 60-95 days to harvest, and is not frost hardy.
• Cucumbers use May-June outdoor timing, two to three weeks to transplant size, 5-10 germination days, 50-70 days to harvest, and are not frost hardy.
• Tomatoes use May-June outdoor timing, five to seven weeks to transplant size, 55-90 days to harvest, and are not frost hardy.
• Watermelon uses May-June outdoor timing, three to four weeks to transplant size, 7-12 germination days, 80-130 days to harvest, and is not frost hardy.
• For succession planting with an average mid-September frost, the guide lists Green Beans July 10, Carrots July 7-15, Cucumbers July 15, Peas July 15, Beets July 15, Summer Squash July 20, and Radish Aug. 20.
• The guide says a South Dakota fall garden is planted from late-June to August, depending on days to maturity and when heavy frost occurs in the fall.
• Use these priority catalog links as crop-row examples only; variety-specific details remain tied to each seed entry's own source.

Catalog crop examples

These catalog entries match crops covered by the regional timing source; variety-specific details remain tied to each seed entry's own source.

• Provider Bush Bean Vegetable · Warm · 50 days
• Detroit Dark Red Beet Vegetable · Cool · 58 days
• Waltham 29 Broccoli Vegetable · Cool · 74 days
• Golden Acre Cabbage Vegetable · Cool · 64 days
• Danvers 126 Carrot Vegetable · Shoulder · 70 days
• Snowball Y Cauliflower Vegetable · Cool · 70 days
• Golden Bantam Sweet Corn Vegetable · Warm · 80 days
• Marketmore 76 Cucumber Vegetable · Warm · 58 days
• Black Beauty Eggplant Vegetable · Warm · 80 days
• Early White Vienna Kohlrabi Vegetable · Cool · 55 days
• Black Seeded Simpson Lettuce Vegetable · Cool · 45 days
• Hale's Best Jumbo Melon Vegetable · Warm · 85 days
• Evergreen Bunching Onion Vegetable · Shoulder · 65 days
• Hollow Crown Parsnip Vegetable · Cool · 120 days
• Sugar Snap Pea Vegetable · Cool · 62 days
• California Wonder Pepper Vegetable · Warm · 72 days
• Small Sugar Pumpkin Vegetable · Warm · 100 days
• French Breakfast Radish Vegetable · Cool · 28 days
• Waltham Butternut Squash Vegetable · Warm · 95 days
• Roma Tomato Vegetable · Warm · 76 days
• Purple Top White Globe Turnip Vegetable · Cool · 55 days
• Sugar Baby Watermelon Vegetable · Warm · 80 days

Related regional guides

• Nebraska Frost-Date and Soil Temperature Vegetable Garden Nebraska Extension timing for east, central, and west frost dates, soil-temperature readiness, rotation families, and frost-relative vegetable planting groups.
• North Dakota Small-Space Frost Vegetable Garden NDSU small-space vegetable guide for North Dakota frost timing, easy crops, containers, watering, close rows, and succession planting.

Source: SDSU Extension Vegetable Gardening in South Dakota