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First and Last Frost Dates and the Garden Growing Season

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The last frost date in spring and the first frost date in autumn mark the beginning and end of the natural garden growing season. Use these dates to plan seed starting, transplanting, and harvesting.

The time to plant seeds in the garden or start seeds indoors depends on the plants you want to grow and their tolerance to frost. The average date of the last frost in your region can be used to determine when a crop can be planted outdoors, or started indoors.

The average date of the last frost in spring and the number of days in the growing season before the first frost in autumn are important starting points when sowing seeds indoors or out.

White frost crystals on Brussels sprouts
White frost crystals on Brussels sprouts

Cool-season crops grow best in the cool weather of spring and autumn–near the frost dates. Warm-weather crops grow best in the late spring and summer months well after the last frost and before the first frost.

Seed starting should be matched to the appropriate time that the variety you are planting will grow. The goal is to bring plants to harvest when the temperatures are optimal to complete their growth cycle or ripen fruit. Planting and harvesting are commonly determined by the number of days between the last frost in spring and the first frost in autumn–this period is known as the growing season.

The average date of the last frost

The average date of the last frost in spring is a day around which you can plan to start seeds indoors, sow seeds in the garden, and set transplants into the garden.

The average date of the last frost in your garden or region is an approximation. It is a date based on an average of the last frost date for each of the last 30 or so years. It is an average or approximation – a date that will change from year to year depending on the weather.

The average date of the last frost is important because most warm-weather plants will not grow and many will die if they are hit by frost. Warm-weather plants most often succeed when they go into the garden two or three weeks after the last frost. By that time daytime temperatures have begun to significantly warm above freezing.

Most cool-weather plants can withstand a light frost. They can be started in the garden a week or two before the last frost in spring or on the date of the last frost in spring.

The average date of the last frost in spring for your regions is available from the nearest cooperative extension. You will also find the last frost date in many gardening books or online from The National Climatic Data Center of the United States government which produces a freeze-frost probability table for each state and the largest cities and towns in each state, and from which produces a chart of high and low-temperature averages by month broken out by zip code and city name.

Know the length of the growing season

The length of the growing season in a garden or region is most often expressed as the average number of frost-free days between the last frost in spring and the first frost or hard freeze in autumn. By the date of the last frost in spring, daytime temperatures have grown significantly warmer than freezing.

A more useful measure of the growing season might be soil temperature averages: the date in spring when the soil temperature averages 40°F or greater (when cool-weather plants begin growth) and the last date in autumn when the soil temperature drops below 40°F (when cool-weather plants stop growth).

Soil temperature in spring may lag by days and weeks behind the air temperature as the soil and collected soil moisture warm after the winter chill. (Soil temperature is affected by solar heat, air temperature, and soil moisture.) The soil generally cools more slowly in autumn for the same reasons (residual solar heat remains in the soil from the summer season and the soil is generally drier in autumn than in spring).

The true growing season for a region or garden is the total number of consecutive days that the soil is warm enough to grow plants–including germination, maturation, and ripening before a killing frost or freeze. Minimum soil temperature is required for a plant to germinate and grow; minimum soil and air temperature is required for growth; the flowering temperature (required for fruiting vegetables) will be higher than the minimum growth temperature.

Use the length of the growing season in your garden to set planting dates for early, mid-season, and late-season crops. Use the length of the growing season to plan succession crops; cool-weather spring crops, followed by warm-weather summer crops, followed by cool-weather autumn crops. If you grow crops without protecting them from killing temperatures, your growing season will be determined by nature.

You can get more from your garden by protecting plants and giving them an artificially warm environment in which to grow. This is called growing season extension.

Keep the following growing season information in mind:

  • Cool-weather vegetables require a minimum average soil temperature of 40° to 50°F for planting and an average air temperature range of 60° to 85°F (optimal is 70°F) for sustained growth. The maximum air temperature for cool-weather crop productivity is 86°F, above this temperature cool-weather crops will bolt or quit growing.
  • Warm-weather vegetables require a minimum average soil temperature of 50°F for planting and an average minimum air temperature of 75°F for sustained growth. The maximum air temperature for warm-weather crop productivity is 110°F, above this temperature most warm-weather crops will die, just as they are likely to die at 32°F.
  • Temperature affects a plant’s rate of growth. The higher the soil and air temperature above the minimum, the faster a plant will grow.
  • Plant growth time: two-thirds of the growth time necessary for a plant to reach harvest and maturity should be at or above the optimal air temperature; the remaining one-third should be between the minimum and optimal temperature.
Cabbage growing in late autumn after a night of frost
Cabbage growing in late autumn after a night of frost

Predicting frost in the garden

Frost in the garden happens when the surfaces of plant leaves or fruit—or other solid objects in the garden—are colder than freezing and moisture in the air condenses on the surfaces to form ice crystals. A light frost or white frost happens when the air temperature drops to around 32°F. If you know frost is coming, you can protect plants with plant blankets, floating row covers, plastic tunnels, or even a cardboard box set over the top of plants.

Three signs frost is likely

  1. The night is clear and bright stars are easily visible. (Clouds act as a blanket of protection against frost keeping ground warmth from escaping into the night.)
  2. The air is dry before midnight with no condensation on car windows or outdoor furniture. (Moisture in the air releases heat when it condenses to form dew; this will prevent frost from forming if the air temperature is just above 32°F–but will result in frost when the air temperature drops below freezing.)
  3. The temperature is 45°F or colder by 10 p.m. (You can expect the overnight temperatures to continue to drop and be the coldest just before dawn.)

Protecting plants from frost

Plants under a solid surface such as cloth, plastic, or cardboard—or under the overhand of a building–are less likely to be damaged by a light frost. Cold air is dense; its molecules are tightly packed. Cold air will sink or flow to the lowest point it can, but it cannot move through solid surfaces. (For tips on protecting plants from frost and freezing weather click here to read Season Extension articles.)

Reviving plants hit by frost

Sprinkle plants touched by frost with water from the hose before the sun shines on them. Heat in the water will raise the air temperature around plants and the temperature of plant tissue. After a frost, don’t assume damaged plants are dead. Let plants sit for a week, then remove only tissue that is clearly dead. Leave perennials alone until their normal period of growth begins, then prune out dead plants. In many areas, the first frost is followed by days of warmer weather. It is worth the effort to get plants past the first cold snap; there may be more harvest to come before the first solid freeze. For a list of crops that can survive frost click her to read Vegetable Garden Plant Hardiness.

Cabbage seedlings
Cabbage seedlings are protected from late winter cold under row cover tunnel

How to extend the growing season

When soil and air temperatures fall below the average and minimum for growing, you can extend the growing season by protecting plants from cold and wind (the combination of wind and low temperatures can be lethal to plants) and by keeping soil and air temperatures at or near the temperatures required for growing. This is achieved with cloches, plastic tunnels, cold frames, hotbeds, and greenhouses. Conversely, when temperatures rise too high for growth, moderate the temperature and protect plants with shade structures, shade cloth, and additional water.

Season extending options

  • Use inexpensive plant covers to thwart frost (these will raise the temperature by 2° to 3°F): paper bags with bottoms cut out; cardboard boxes turned upside down; milk cartons or plastic jugs with the bottoms cut out; buckets turned over; hats made of newspaper.
  • Use more substantial covers can raise the covered temperature by 5° to 15°F:
  • Vertical tomato wire cages wrapped in plastic.
  • • Wooden A-frames covered with sheets of polyethylene.
  • • Fencing or chicken wire arched across planting beds to form tunnels covered with plastic and held in place with staples or clothespins.
  • Arched panels of ribbed translucent fiberglass.
  • Hoop or wicket tunnels covering an entire bed: wickets or hoops of stiff wire arched and covered with clear polyethylene.
  • Cold frames and hotbeds. A cold frame or hotbed can raise the temperature of protected beds by 20°F or more and extend the growing season by several months to all year. A cold frame or hotbed is a box with a plastic or glass top that captures the warming rays of the sun and holds the heat.
  • Use 2 x 8 or 2x 10-inch board to form an open-bottomed box that will fit over your crops. (The top can be made less expensively with two layers of polyethylene.) Cut one end of the box to slant towards the sun, or place soil under the north end of the box so that it slants towards the sun and captures the solar heat.
  • A hotbed is a heated cold frame. Dig a pit 18 inches deep and place fresh horse or cow manure in the pit or freshly cut grass or green manure. Place one inch of sand and 6 inches of soil over the organic matter to make a growing bed, or two inches of sand to form a floor on which to place pots or growing flats. The bacterial action of the organic matter decomposition will heat the frame. A hot frame also can be heated by placing light bulbs in the frame or soil heating cables.
  • On warm sunny days, air temperature in cold frames, hotbeds, and under plastic tunnels can quickly become too hot. Ventilation–simply opening the top or lifting the cover–is required to keep plants from suffering from too much heat.

Nearly all forms of plant protection can increase the number of growing days by at least three or four weeks in both spring and autumn. That is a significant boost to the growing season. The combination of the extended growing season and higher temperatures will allow the growing of semi-tropical vegetables such as tomatoes, peppers, and eggplants.

How to use last and first frost dates

Average frost dates–the last frost in spring and the first frost in autumn–can be used to set seed starting dates for the crops you plan to grow. They can also be used to set harvest dates and to plan the extension of the growing season–both early and late.

Most crops grow best during the frost-free days of the year. The days between the last frost in spring and the first frost in autumn make up the growing season. The growing season differs from region to region–longer in southern regions, and shorter in northern regions.

The average date of the last and first frost allows you to estimate the length of your growing season. You can use the average date of the last and first frost to plan when seeds can be started in the garden when seeds should be started earlier indoors, and when seedlings started indoors can be set out in the open garden. Since most vegetables and herbs suffer when hit by frost, the average date of the last and first frost is very important.

The average dates of the last and first frost are estimates. They are based on historical averages, average dates kept by weather services, and state and federal agriculture agencies. These averages are commonly used as guidelines for planting and harvesting. Climate, weather, and growing season days can change from year to year so also averages can only be used to approximate when to plant or harvest.

USDA map

USDA hardiness zones

In addition to the last and first average frost dates, hardiness zones are helpful to gardeners.

A plant’s “hardiness” generally refers to its ability to survive winter temperatures. A plant that is considered hardy in Florida but cannot withstand winter low temperatures in Maine is not hardy to Maine. Hardiness zones were developed to help gardeners determine which plants can survive the minimum temperatures of a particular region.

Plant hardiness zones have been developed by the United States Department of Agriculture. There are 11 growing zones in the United States, zones 1-11. Zone 1 in Alaska has the coldest annual minimum temperatures (lows below -50°F) and Zone 11 in South Florida (lows above 40°F) is the warmest. Hardiness zones are further divided into “A” and “B”; “A” is the less warm region of the zone and “B” is the warmer region of the zone.

You can use last and first frost dates to help determine when the best time to plant a crop. You can use hardiness zones to know how cold a place can get and which plants can survive there. There is an indirect correlation between the average frost dates and hardiness zones.

Other growing factors

Successful growing is also determined by the garden soil type, rainfall or irrigation, daytime temperature, nighttime temperature, day length, wind, humidity, and heat. Climates and growing conditions can vary even if they are in the same growing zone. Use the zones as a starting point, not as the final determinant of what will grow in your garden.

Average first and last frost dates by state and city

Here are the average last frost dates, average first frost dates, average days in the growing season, and USDA zone for several cities in the United States, Canada, and other parts of the world.

United States

State and city         Last frost          First frost            Days         Zone   


Birmingham       March 19                  November 14          241                 7B

Mobile                 February 17              December 12          298                 8A

Montgomery      February 27              December 3            279                 8A


Anchorage          May 18                      September 13          118                 4

Barrow                June 27                     July 5                           8                  4

Cordova              May 10                      October 2                145                  4

Fairbanks           May 24                     August 29                  97                  4


Flagstaff             June 8                       October 2                116                 5B

Phoenix              January 27               December 11           317                 9A

Tucson               March 12                  November 21           225                 8A

Winslow            April 28                     October 21               176                 5B


Fort Smith          March 23                 November 9            231                 8B

Little Rock          March 16                 November 15          244                 7A

Pine Bluff            March 26                 November 5            224                 7B

Texarkana           March 21                 November 19          233                 7B


Bakersfield         February 14             November 28          287                 8B

Eureka                 March 10                  November 18          253                  8B

Fresno                 February 3                December 3            303                  8A

Los Angeles        January 3                  December 28          359                 10

Marysville           February 21              November 21          273                 7B

Palm Springs      January 8                 December 18          334                 9B

Pasadena             February 3                December 13          313                 9B

Red Bluff             March 6                     December 5            274                 7B

Riverside             March 6                     November 26         265                 8B

Sacramento         January 24               December 11          321                  8B

San Diego            no frost                       no frost                  365                  10

San Francisco     January 7                  December 29         356                  8B

San Jose              February 10              January 6                299                 8B

Santa Barbara    January 22                December 19          331                 8B                                                                     Santa Rosa          April 10                       November 3          207                 8B


Denver               May 2                       October 14              165                 5A

Grand Junction  April 20                    October 9                173                 6A

Pueblo                April 28                    October 12              167                 5B


Bridgeport          April 26                    October 16              174                 6A

Hartford             April 22                    October 19              180                 5A

New Haven        April 15                    October 25              193                 6A


Dover                   April 17                    October 22              188                 7A

Newark                April 20                    October 17              180                 7A

Wilmington        April 18                    October 26              191                 7A

District of Columbia

Washington        April 10                    October 28              200                 9A


Jacksonville       February 6                December 16          313                 8B

Miami                 irregular frost           irregular frost          365                 10

Orlando              January 31                December 17          319                 9B

Tallahassee        February 26              December 3            280                 8B

Tampa                January 10                December 26          349                 9A


Atlanta               March 20                  November 19          244                 7B

Augusta             March 14                  November 1            249                 7B

Macon                March 12                  November 19          252                 7B

Savannah          February 21              December 9            291                 8B


Hilo                    no frost                     no frost                   365                 10         `

Honolulu           no frost                     no frost                   365                 10


Boise                  April 29                    October 16              171                 6A

Coeur d’Alene   May 12                     October 14              155                 5B

Pocatello            May 8                       September 20          155                 4


Cairo                  March 23                  November 11          233                 6A

Chicago              April 19                    October 28              192                 5B

Rockford            May 7                       October 11              157                 5A

Springfield         April 8                      October 30              205                 5B

Urbana               April 22                    October 20              151                 5B


Evansville          April 2                      November 4            216                 6A

Fort Wayne        April 24                    October 20              179                 5B

Indianapolis       April 17                    October 27              193                 5B


Des Moines       April 20                    October 19              183                 5A

Dubuque            April 19                    October 19              184                 5A

Mason City        April 25                    September 25          153                 4

Sioux City          April 27                    October 13              169                 4


Concordia          April 16                    October 24              191                 5B

Topeka               April 9                      October 26              200                 5B

Wichita               April 5                      November 11          210                 6A


Lexington           April 13                    October 28              198                 6A

Louisville           April 1                      November 7            220                 6B


Lake Charles      February 18              December 6            291                 8B

New Orleans      February 13              December 12          302                 9A

Shreveport         March 1                    November 27          272                 8A


Bangor               May 1                       October 4                156                 5A

Caribou              May 19                     September 21          125                 4

Greenville          May 27                     September 20          116                 5A

Portland             April 29                    October 15              169                 5A

Presque Isle       May 31                     September 18          110                 4


Baltimore           March 28                  November 17          234                 7A

Cumberland       May 1                       October 10              163                 6A

Salisbury            April 20                    October 20              183                 7A


Amherst             May 12                      September 19          130                 5B

Boston               April 16                      October 25              192                 6A

Fall River           April 22                     October 23              184                 6A

Nantucket          April 12                     November 16          219                 6A

Pittsfield             May 12                      September 27          138                 5B

Worcester           May 7                       October 2                148                 5B


Detroit                 April 25                    October 23              181                 5B

Escanaba             May 14                     October 6                145                 4

Grand Rapids    April 25                    October 30              190                 5B

Lansing               May 6                       October 8                155                 5B

Marquette           May 13                     October 19              159                 4


Albert Lea          May 3                       October 6                156                 4

Duluth                May 22                     September 24          125                 3

Minneapolis      April 30                    October 13              166                 4

Virginia              May 29                     September 14          108                 3


Biloxi                  February 22              November 28          279                 8B

Jackson              March 10                  November 13          248                 7B

Tupelo                March 31                  October 28              211                 7B

Vicksburg          March 8                    November 15          252                 7B


Columbia            April 9                      October 24              198                 5B

Kansas City        April 5                      October 31              210                 5B

Saint Joseph      April 11                    October 14              186                 5B

St. Louis             April 2                      November 8            220                 5B

Springfield         April 13                    October 20              190                 6A


Billings              May 15                     September 24          132                 4

Glasgow            May 19                     September 20          124                 3

Great Falls        May 9                       September 25          139                 4

Havre                 May 9                       September 23          138                 4


Lincoln               April 20                    October 17              180                 5A

Norfolk               May 4                       October 3                152                 5A

North Platte       April 30                   October 7                160                 5A

Omaha                April 14                    October 20              189                 5A


Elko                   June 6                       September 3            89                   5A

Las Vegas          March 13                  November 13          245                 7A

Reno                  May 14                      October 2                141                 5B

New Hampshire

Berlin                 May 29                     September 15          109                 4

Concord             May 11                      October 1                143                 5A

Errol                   June 1                       September 5            96                   4

New Jersey

Atlantic City      March 31                  November 11          225                 6B

Cape May          April 4                      November 13          222                 6B

New Brunswick April 21                   October 19              179                 6A

Newark              April 3                      November 8            219                 6A

Trenton              April 8                      November 5            211                 6B

New Mexico

Albuquerque      April 16                    October 29              196                 7A

Roswell               April 9                      November 2            208                 7A

Santa Fe             April 23                    October 19              179                 5A

New York

Albany               April 27                    October 13              169                 5A

Binghamton      May 4                       October 6                154                 5A

Buffalo               April 29                    October 23              178                 5B

New York City  April 7                      November 12          219                 6B

Syracuse            April 30                    October 15              168                 5A

Watertown         May 7                       October 4                151                 5A

North Carolina

Asheville            April 12                    October 24              195                 7A

Charlotte            March 21                  November 15          239                 7B

Raleigh               March 24                  November 16          237                 7B

Wilmington        March 15                  November 19          274                 7B

Winston Salem  April 14                    October 24              193                 7A

North Dakota

Bismarck            May 11                     September 24          136                 4

Fargo                  May 13                     September 27          137                 4

Williston            May 14                     September 23          132                 3


Cincinnati           April 15                    October 25              192                 6A

Cleveland           April 21                    November 2            195                 5B

Columbus          April 17                    October 30              196                 5B

Dayton               April 20                    October 21              184                 5B

Toledo                April 24                    October 25              184                 5B


Miami                April 7                      October 26              202                 6A

Oklahoma City  March 28                  November 7            223                 7A

Tulsa                  March 31                  November 2            216                 6B


Bend                  June 8                       September 7            91                   5B

Eugene              April 13                     November 4            205                 7B

Medford            April 25                    October 20              178                 7B

Portland            February 25             December 1            279                 8A

Salem                 April 14                     October 27              197                 7B


Altoona              May 6                       October 4                151                 5B

Erie                    May 1                         October 11              163                 5A

Harrisburg        April 10                    October 28              201                 6A

Philadelphia     March 30                 November 17          232                 6B

Pittsburgh         April 20                    October 23              187                 6A

Scranton            April 24                    October 14              174                 5B

Williamsport     May 3                       October 13              164                 5B

Rhode Island

Kingston             May 1                       October 14              166                 6A

Providence         April 13                    October 27              197                 6A

South Carolina

Charleston          February 19              December 10          294                 8A

Columbia            March 14                  November 21          252                 7B

Greenville           March 23                  November 17          239                 7B

South Dakota

Huron                 May 4                       September 30          149                 5A

Rapid City          May 7                       October 4                150                 5A

Sioux Falls         May 5                       October 3                152                 5A


Chattanooga       March 26                  November 11          229                 7A

Knoxville             March 31                  November 6            220                 6B

Memphis            March 20                  November 12          237                 7A

Nashville            March 28                  November 7            224                 6B


Brownsville       February 15              December 10          298                 9A

Corpus Christi   January 26              December 27          335                 9A

Dallas                  March 18                  November 22          249                 8A

El Paso               March 26                  November 14          238                 8B

Houston             February 5                December 11          309                 8B

Lubbock             April 1                       November 9            205                 7A

Plainview           April 10                     November 6            211                 7B


Blanding             May 18                     October 14              148                 6B

Logan                  May 15                     October 6                144                 6B

Ogden                 April 13                    October 22              192                 6B

Salt Lake City    April 12                    November 1            202                 6B


Bennington        May 15                     October 4                142                 5A

Burlington          May 8                       October 3                148                 4

St. Johnsbury     May 22                    September 25          126                 3


Norfolk              March 18                  November 27          254                 7B

Richmond          April 2                      November 8            220                 7A

Roanoke             April 20                    October 24              187                 7A


Centralia            April 27                    October 7              173                 7B

Seattle                February 23             December 1            281                 7B

Spokane             April 20                    October 12              175                 5B

Walla Walla      April 3                      November 1            211                 5B

Yakima              April 15                     October 22              190                 6A

West Virginia

Charleston          April 18                    October 28              193                6B

Martinsburg       April 29                    October 16              170                6B

Parkersburg       April 16                    October 21              189                 6A


Green Bay          May 6                       October 13              161                 5A

Lacrosse             May 1                        October 8                161                 4

Madison             April 26                    October 19              177                 5A

Milwaukee         April 20                    October 25              188                5B


Casper                May 18                     September 25          130                 4

Cheyenne           May 20                     September 27          130                4

Sheridan             May 21                     September 21          123                 4

Puerto Rico

All locations       no frost                     no frost                   365                 10

Virgin Islands

All locations      no frost                     no frost                   365                 10



Calgary              May 28                     September 9            104                 3

Edmonton         May 14                     September 14          123                 3

British Columbia

Prince George    June 10                     August 28               79                   3

Victoria               February 28              December 9           284                7B


Churchill            June 26                     September 12          82                 2

Winnipeg           May 25                     September 21          119                 3

New Brunswick

Fredericton         May 18                     September 26          130                 4


Saint John’s       June 3                       October 12              131                 5A

Northwest Territories

Yellow Knife     May 30                     September 16          109                 2

Nova Scotia

Halifax               May 15                     October 15              153                 5B


Toronto              April 20                    October 30              193                 5B

Prince Edward Island

Charlottetown    May 17                     October 15              151                 5A


Montreal            May 3                       October 17              155                 4

Quebec City       May 18                     September 18          123                 4


Regina                May 27                     September 12          108                 5B


Dawson             May 26                     August 27               93                   4

Growing Zones throughout the World

Country and city             Zone       Minimum


Buenos Aires                     9

Cordoba                             9


Adelaide                             10                   Australia zone 4

Brisbane                             10                  Australia zone 4

Melbourne                          10                 Australia zone 4

Perth                                   10                  Australia zone 4

Sydney                               10                  Australia zone 4


Vienna                                6


Brussels                             8


Santiago                             10


Beijing                                7

Hong Kong                        10

Shanghai                            9


Lyon                                   8

Paris                                   8

Marseille                           9


Berlin                                 6

Frankfurt                           7

Hamburg                           7

Munich                              6


Belfast                                9

Dublin                                8

Galway                               9


Florence                             9

Milan                                  8

Palermo                            10

Rome                                  9

Venice                                8


Sapporo                             6

Kyoto                                 9

Tokyo                                 9

New Zealand

Auckland                            10

Christchurch                       9

Wellington                         10

South Africa

Cape Town                        11

Durban                               11

Johannesburg                    9


Barcelona                          10

Cordoba                             9

Madrid                               9

Seville                                10

Valencia                             10

United Kingdom

Bristol                                9

Glasgow                             8

Inverness                           8

Leeds                                  8

Liverpool                           9

London                               8


Montevideo                       10

Garden Planning Books at Amazon:

Written by Stephen Albert

Stephen Albert is a horticulturist, master gardener, and certified nurseryman who has taught at the University of California for more than 25 years. He holds graduate degrees from the University of California and the University of Iowa. His books include Vegetable Garden Grower’s Guide, Vegetable Garden Almanac & Planner, Tomato Grower’s Answer Book, and Kitchen Garden Grower’s Guide. His Vegetable Garden Grower’s Masterclass is available online. has more than 10 million visitors each year.

How To Grow Tips

How To Grow Tomatoes

How To Grow Peppers

How To Grow Broccoli

How To Grow Carrots

How To Grow Beans

How To Grow Corn

How To Grow Peas

How To Grow Lettuce

How To Grow Cucumbers

How To Grow Zucchini and Summer Squash

How To Grow Onions

How To Grow Potatoes

December Flower Garden Tips Zone-by-Zone

Average First and Last Frost Dates for Cities, States, and Countries