| 0 | 2106200 | WLP 2490 | Angus Gholson Nature Park | Hydrangea quercifolia W. Bartram | Florida, United States | Not Available |  | -15 | sdev=3.48866; sample size=65 | Standard error is reported here rather than standard deviation. The warmest temperature tested in March was -15°C. | WLP 2490 ** |
| 1 | 2106215 | WLP 2505 | Old U.S. 84 | Hydrangea quercifolia W. Bartram | Mississippi, United States | |  | -15 | sdev=5.57304; sample size=47 | Standard error is reported here rather than standard deviation. The warmest temperature tested in March was -15°C. | WLP 2505 ** |
| 2 | 2106217 | WLP 2507 | LeFleur's Bluff State Park | Hydrangea quercifolia W. Bartram | Mississippi, United States | |  | -15 | sdev=53.9021; sample size=59 | Standard error is reported here rather than standard deviation. The warmest temperature tested in March was -15°C. | WLP 2507 ** |
| 3 | 2151676 | NA 79211 | 'Pee Wee' | Hydrangea quercifolia W. Bartram | 0 | Not Available | | -15 | sdev=55.428; sample size=33 | Standard error is reported here rather than standard deviation. The warmest temperature tested in March was -15°C. | NA 79211 ** |
| 4 | 1910274 | PI 668118 | 'Queen of Hearts' | Hydrangea quercifolia W. Bartram | Tennessee, United States | Not Available | | -17.2516 | sdev=5.95511; sample size=30 | Standard error is reported here rather than standard deviation. | PI 668118 ** |
| 5 | 2150927 | NA 77101 | 'Flemygea' | Hydrangea quercifolia W. Bartram | 0 | Not Available | | -18.0386 | sdev=5.17969; sample size=45 | Standard error is reported here rather than standard deviation. | NA 77101 ** |
| 6 | 2106228 | WLP 2518 | River Bluff Recreational Area | Hydrangea quercifolia W. Bartram | Georgia, United States | |  | -18.0696 | sdev=3.18394; sample size=67 | Standard error is reported here rather than standard deviation. | WLP 2518 ** |
| 7 | 2106213 | WLP 2503 | Jeff Busby Park | Hydrangea quercifolia W. Bartram | Mississippi, United States | |  | -21.0654 | sdev=2.05523; sample size=53 | Standard error is reported here rather than standard deviation. | WLP 2503 ** |
| 8 | 2106210 | WLP 2500 | Trace State Park | Hydrangea quercifolia W. Bartram | Mississippi, United States | |  | -22.2647 | sdev=2.06909; sample size=65 | Standard error is reported here rather than standard deviation. | WLP 2500 ** |
| 9 | 2106209 | WLP 2499 | Rock Island State Park | Hydrangea quercifolia W. Bartram | Tennessee, United States | | | -22.3164 | sdev=2.47397; sample size=56 | Standard error is reported here rather than standard deviation. | WLP 2499 ** |
| 10 | 2106253 | WLP 2543 | Red Bluff | Hydrangea quercifolia W. Bartram | Mississippi, United States | |  | -22.3719 | sdev=2.22982; sample size=61 | Standard error is reported here rather than standard deviation. | WLP 2543 ** |
| 11 | 2150926 | NA 77100 | 'Alice' | Hydrangea quercifolia W. Bartram | 0 | Not Available | | -22.6945 | sdev=3.71189; sample size=45 | Standard error is reported here rather than standard deviation. | NA 77100 ** |
| 12 | 2106226 | WLP 2516 | Solon-Dixon Forestry Center | Hydrangea quercifolia W. Bartram | Alabama, United States | |  | -23.7846 | sdev=1.12335; sample size=66 | Standard error is reported here rather than standard deviation. | WLP 2516 ** |
| 13 | 2106258 | WLP 2548 | Choctaw Wildlife Management Area | Hydrangea quercifolia W. Bartram | Mississippi, United States | |  | -25.4837 | sdev=1.84772; sample size=66 | Standard error is reported here rather than standard deviation. | WLP 2548 ** |
| 14 | 2106244 | WLP 2534 | Rocky Branch Public Use Area | Hydrangea quercifolia W. Bartram | Alabama, United States | |  | -25.8324 | sdev=1.39244; sample size=66 | Standard error is reported here rather than standard deviation. | WLP 2534 ** |
| 15 | 2106246 | WLP 2536 | James H. Floyd State Park | Hydrangea quercifolia W. Bartram | Georgia, United States | |  | -26.3477 | sdev=2.54839; sample size=68 | Standard error is reported here rather than standard deviation. | WLP 2536 ** |
| 16 | 1826732 | PI 658494 | 'Munchkin' | Hydrangea quercifolia W. Bartram | Tennessee, United States | Not Available | | -26.7341 | sdev=3.14169; sample size=32 | Standard error is reported here rather than standard deviation. | PI 658494 ** |
| 17 | 2106235 | WLP 2525 | Chewacla State Park | Hydrangea quercifolia W. Bartram | Alabama, United States | Not Available |  | -26.9063 | sdev=1.65565; sample size=59 | Standard error is reported here rather than standard deviation. | WLP 2525 ** |
| 18 | 2106203 | WLP 2493 | Gullets Bluff Park | Hydrangea quercifolia W. Bartram | Alabama, United States | |  | -27.9336 | sdev=1.83829; sample size=57 | Standard error is reported here rather than standard deviation. | WLP 2493 ** |
| 19 | 2106234 | WLP 2524 | Coon Creek Forever Wild Tract | Hydrangea quercifolia W. Bartram | Alabama, United States | |  | -29.87 | sdev=2.04402; sample size=59 | Standard error is reported here rather than standard deviation. | WLP 2524 ** |
| 20 | 2106205 | WLP 2495 | Natural Bridge Park | Hydrangea quercifolia W. Bartram | Alabama, United States | |  | -29.8826 | sdev=2.01202; sample size=48 | Standard error is reported here rather than standard deviation. | WLP 2495 ** |
| 21 | 2106232 | WLP 2522 | Oakmulgee Ranger District | Hydrangea quercifolia W. Bartram | Alabama, United States | |  | -29.9479 | sdev=2.44413; sample size=65 | Standard error is reported here rather than standard deviation. | WLP 2522 ** |
| 22 | 1826731 | PI 658493 | 'Ruby Slippers' | Hydrangea quercifolia W. Bartram | Tennessee, United States | Not Available | | -30.6906 | sdev=2.13286; sample size=47 | Standard error is reported here rather than standard deviation. | PI 658493 ** |
| 23 | 2106220 | WLP 2510 | Tunica Hills | Hydrangea quercifolia W. Bartram | Louisiana, United States | |  | -30.7952 | sdev=2.2537; sample size=70 | Standard error is reported here rather than standard deviation. | WLP 2510 ** |
| 24 | 2106222 | WLP 2512 | Kisatchie National Forest | Hydrangea quercifolia W. Bartram | Louisiana, United States | |  | -31.8812 | sdev=2.19064; sample size=48 | Standard error is reported here rather than standard deviation. | WLP 2512 ** |
| 25 | 2106245 | WLP 2535 | Little River Canyon | Hydrangea quercifolia W. Bartram | Alabama, United States | |  | -34.4077 | sdev=9.46503; sample size=47 | Standard error is reported here rather than standard deviation. | WLP 2535 ** |
| 26 | 2106204 | WLP 2494 | Oak Mountain State Park | Hydrangea quercifolia W. Bartram | Alabama, United States | |  | -35 | sdev=3.40101; sample size=95 | Standard error is reported here rather than standard deviation. The coldest temperature tested in March was -35°C. | WLP 2494 ** |