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USDA Zones, Frost Dates & Calendar FoundationsMonthly Garden Task Calendar by Zone
Monthly task lists are handy, but a list written for another zone or state can send you out at the wrong time. This guide shows how to build one that fits your site.
Key points
- Zones do not give frost dates or monthly tasks.
- Start from your own state's extension calendar.
- Write tasks as offsets from frost dates and soil conditions.
- Update the calendar with real dates every year.
Why can a zone-based monthly list mislead you?
The USDA Plant Hardiness Zone Map reports average annual extreme minimum temperature. It does not report frost dates, rainfall or growing season length. Two places in the same zone can have last frost dates weeks apart.
A month name also means something different in Florida than in Minnesota. Treat any generic list as a template to adapt.
Beyond hardiness zones, other tools such as frost probability tables give much better guidance about the dates that matter to a gardener.
What do good extension monthly guides look like?
State extension programs publish monthly or seasonal garden calendars written for their own climate, such as those from Oregon State and the University of Tennessee. They list tasks by month for their state or region, and they are a better starting point than a national list.
Look for the guide from your own state, ideally from the extension office nearest you. If your region spans several climates, check whether the guide splits by area.
State calendars often vary within a state, so look for the one nearest your county.
- Prefer your own state's extension calendar
- Check which region of the state it was written for
- Note which month names depend on frost dates
How do you convert months into frost-based tasks?
Replace month names with offsets from your frost dates. For example, write 'sow peas as soon as soil can be worked' and 'set tomato transplants after the last spring frost and when nights are warm' instead of naming a month.
Then place those tasks on your calendar using your own frost probability dates. The offsets will carry across years, while the month names would not.
Soil temperature thresholds are a useful addition, because each crop has a minimum for sowing and a more comfortable range for growth.
What tasks belong in each season?
Winter: planning, ordering seed, soil tests, equipment repair and pruning of dormant fruit trees as local guidance advises. Early spring: testing soil workability, starting transplants and sowing hardy crops. Late spring: transplanting tender crops after frost risk, mulching and watering plans.
Summer: weeding, watering, scouting for pests and succession sowing for fall. Fall: planting garlic where suitable, cover crops, harvesting storage crops and cleaning up. Adjust each item for your climate.
Keep the list short enough to follow. A task list of a dozen items per month is easier to keep than one of fifty.
How do you add soil testing and nutrient timing?
Schedule a soil test at a consistent time each year, since results compare better from year to year. Use the results and local recommendations to plan any lime or fertilizer. Rates and timing vary by soil, crop and state, and some states have nutrient management rules.
Do not guess. Your extension office can explain how to sample and where to send samples.
Test the soil in the same season each year so the results compare, and keep each report with the others. Revisit the list each season and add the crops that you tried and the dates that worked, so the calendar moves steadily closer to your own site.
What about pest and disease tasks?
Add scouting to the calendar as a task rather than spraying on a schedule. University pest programs publish timing cues, and degree day or plant stage signals help.
This calendar gives education only. Label directions are the law, pre-harvest intervals apply, and applicator licensing varies by state. Protect pollinators when plants are blooming.
Mark scouting days on the calendar so they become routine, since early detection is far easier to manage than a late discovery.
How do you keep the calendar current?
Each month, write what you did and what the weather did. At year's end, update the task list with actual dates. After a few years, your own calendar will be more reliable than any published one.
Share the finished calendar with whoever helps you, and keep a printed copy where the tools are kept.
Add notes about weather extremes to each month so you can see how unusual a year was. Where you garden with others, such as a community plot or a school garden, agree on one shared calendar with a few key dates and assign tasks to named people. A calendar that is posted where everyone sees it, and updated by one person, avoids duplicate work and missed jobs. Extension master gardener programs often have sample task lists for group gardens.
Sources and further reading
Last reviewed: November 2026. Educational information, ranges only. Confirm timing with your county extension office.