Frost Resistance

See: https://www.extension.purdue.edu/extmedia/ho/ho-203.html

                             VEGETABLES: Frost Resistance 

Very Hardy1  Frost Tolerant2   Tender3      Warm Loving4
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Asparagus    Beet              Snap bean    Lima bean
Collards     Broccoli          Sweet corn   Cucumber
Endive       Brussels sprout   Tomato       Eggplant
Kale         Cabbage                        Muskmelon
Kohlrabi     Carrot                         Okra
Lettuce      Cauliflower                    Pepper
Mustard      Celeriac                       Pumpkin
Onion (sets  Celery                         Squash,
 and seeds)  Chard                           summer
Pea          Chinese cabbage                Squash,
Potato       Jerusalem                       winter
Rhubarb       artichoke                     Sweet
Rutabaga     Onion (plants)                  potato
Salsify      Parsnip                        Watermelon
Spinach      Radish
Turnip

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* Based upon information from University of Illinois publication
VC 14 a2, Vegetable Planting Guide.

1 Very hardy vegetables can withstand freezing temperatures
and hard frosts for short periods without injury. They may be planted
as soon as the ground can be prepared. usually 4 to 6 weeks before the
average frost-free date.

2 Frost tolerant vegetables can withstand light frosts and
can be planted 2 to 3 weeks before the average frost-free date.

3 Tender vegetables are injured or killed by frost, and
their seeds do not germinate well in cold soil. They are usually
planted on or after the average frost-free date.

4 Warm loving vegetables cannot tolerate cold. They require
warm soils for germination and good growth, and should be planted 1 to
2 weeks after the average frost-free date.

                          ANNUAL FLOWERS: Frost Resistance

Very Hardy¹            Frost Tolerant²                    Tender³            Warm Loving⁴

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Cornflower   Bells of Ireland   Aster        Argeratum
Ornamental    (Molucella)       Nicotinia    Balsam
 cabbage     Black-eyed Susan   Petunia      Begonia
Pansy         (Rudbeckia)       Scabiosa     Cockscomb
Primrose     Coreopsis          Statice       (Celosia)
Violet       Pinks (Dianthus)   Sweet        Cosmos
             Pot Marigold        Alyssum     Impatiens
              (Calendula)       Verbena      Lobelia
             Snapdragon                      Marigold
             Stock (Matthiola                Moss Rose
              incana)                         (Portulaca)
             Sweet pea                       Periwinkle
             Torenia                          (Vinca)
                                            Phlox, annual
                                            Salpiglossis
                                            Salvia
                                            Zinnia
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* Based upon information from Purdue University publication HO-14.
Starting Seeds Indoors.

1 Very hardy flowers can withstand freezing temperatures
and hard frosts for short periods without injury. They may be planted
as soon as the ground can be prepared, usually 4 to 6 weeks before the
average frost-free date.

2 Frost tolerant flowers can withstand light frosts and can
be planted 2 to 3 weeks before the average frost-free date.

3 Tender flowers are injured or killed by frost. Transplants
lack vigor in cold soil. and may need to be replaced for desired
floral display.  They are usually planted on or after the average
frost-free date.

4 Warm loving flowers cannot tolerate cold. They require
warm soils for transplants to survive and become established. They
should be planted 1 to 2 weeks after the average frost-free date.