Planting Dates & Climate Calculators
Timing is half of gardening. These tools turn frost dates, temperatures and sunlight into real dates for sowing, planting out and harvesting.

Last Frost Date Calculator
Your average last spring frost and the safe dates to sow and plant out.
Gives yousafe date · spring timelineTimingFirst Frost Date Calculator
Your average first autumn frost and the last dates to sow crops so they mature in time.
Gives yousow-by date · fall crop tableTimingPlanting Calendar
A personal sowing and planting calendar for 19 vegetables from your frost dates.
Gives youindoor sowing · planting out · autumn sowingTimingTransplant Date Calculator
When to sow indoors, harden off and transplant seedlings from your last frost date.
Gives yousow date · harden off · transplantTimingHarvest Date Calculator
When your crop will be ready to pick, from planting date and days to maturity.
Gives youfirst harvest · harvest windowTimingGrowing Degree Days Calculator
Daily and total growing degree days, and how long until your crop's GDD target.
Gives youGDD per day · total · days to targetTimingChill Hours Calculator
Estimated winter chill hours or Utah chill units, compared with your fruit variety's need.
Gives youchill hours · variety checkTimingSun Exposure Calculator
Whether your spot is full sun, part sun, part shade or shade, and what grows there.
Gives yousun category · day length · plant ideasWhich timing calculator do you need?
- Last Frost Date Calculator: Your average last spring frost and the safe dates to sow and plant out.
- First Frost Date Calculator: Your average first autumn frost and the last dates to sow crops so they mature in time.
- Planting Calendar: A personal sowing and planting calendar for 19 vegetables from your frost dates.
- Transplant Date Calculator: When to sow indoors, harden off and transplant seedlings from your last frost date.
- Harvest Date Calculator: When your crop will be ready to pick, from planting date and days to maturity.
- Growing Degree Days Calculator: Daily and total growing degree days, and how long until your crop's GDD target.
- Chill Hours Calculator: Estimated winter chill hours or Utah chill units, compared with your fruit variety's need.
- Sun Exposure Calculator: Whether your spot is full sun, part sun, part shade or shade, and what grows there.
Every tool works in metric or imperial units, shows its formula and a worked example, and lets you edit the assumptions that vary from garden to garden. Results stay on your device; nothing you enter is stored.
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