Vegetable Planting Calendar: How to Read and Adjust It

Use a planting calendar as a starting point, then move every date to your own last-frost date and soil temperature. A calendar made for Georgia is wrong for Minnesota, and our sources are regional extension guides, so each row below comes from a real place or a stated frost rule. This guide shows how to read the bands, puts the windows for our ten crops side by side, and explains how to shift each one. For the soil rule behind most of the warm-season dates, see our guide to soil temperature for planting.

How to read our calendars

Each calendar is a table with a column per month and up to four bands.

• Sow indoors (hatched): seed, or slips, started under cover.
• Transplant out (solid): seedlings or slips moved to the garden.
• Direct sow (dotted): seed, cloves, sets or pieces planted where they grow.
• Harvest (striped): when picking or digging starts. Picking can continue after the band ends.

A blank cell means our sources give no figure, not that the crop is out of season. Months are approximate, and many are our conversion from a frost-relative rule. The note under each calendar says which.

Fall-planted crops

Garlic and shallot go in before winter. The garlic row is UGA’s late September through November window for Georgia, and the harvest months are our arithmetic from “up to 8 months to mature”. The shallot rows are Arkansas Extension’s dates.

Read more in when to plant garlic and when to plant shallots.

Warm-season crops

These wait for warm soil or the end of frost. Rows are either a place (South Carolina, Florida, Iowa), a last-frost date (Apr 15, May 15, Mar 15), or the date the soil reaches 65°F (peanut).

Each crop’s full reasoning is on its page: okra, sweet potato, peanut, edamame and luffa.

Herbs and spices

Ginger, turmeric and lemongrass are frost-tender. Our sources give Hawaii windows, a spring and fall conversion for turmeric, and a frost rule for lemongrass.

See ginger, turmeric and lemongrass for the sources behind each row.

How to adjust by last-frost date

Most of the crops above give a rule relative to frost rather than a date. Apply the rule to your own last-frost date. The last column is a worked example for a last frost on May 1, and it is our arithmetic, not a quote.

Peanut and okra also depend on soil temperature. If the frost rule says go but the soil is cold, wait. Okra needs soil of at least 65°F (18°C) at 4 in. (10 cm) (UGA), and peanut seed wants 65°F at that depth at noon for three days (NC State).

Build your own calendar in five steps

1. Find your last-frost date. Penn State says your county extension office or the National Weather Service gives your frost-free date.
2. Find your first fall freeze. Your state extension office publishes the average. Garlic and shallot are counted back from it.
3. Pick the crop’s rule from the table above, and count forward or back from the frost date.
4. Check the soil before you sow okra, sweet potato or peanut. If the soil is below 65°F (18°C) at 4 in. (10 cm), wait, whatever the date says.
5. Compare your dates with the nearest row. If they differ by more than a few weeks, trust your frost rule and ask a local extension office, because our rows come from specific places.

If you garden between two rows, our ginger guide gives the best rule: use the cooler-area row and let the night temperature, not the calendar, tell you when to move pots outside.

Mistakes a calendar can cause

• Copying another region’s dates. Our garlic page warns against copying Georgia’s dates into a colder state. The principle that travels is Penn State’s: roots before the freeze.
• Sowing by the date. A warm week in April does not mean the soil is ready. Okra seedlings in cold, wet soil are the ones root-decay diseases kill (Clemson).
• Forgetting the harvest deadline. Sweet potatoes come out before the first killing frost (Penn State) and luffa gourds before frost ruins them (Illinois), so count forward as well as back.

What our calendars leave out

We would rather show a gap than a guess. Edamame is one trial, and Utah State says only to plant after frost. Luffa has no harvest months, because gourds can take up to 200 days and must come in before frost. Ginger and turmeric in cooler areas have no harvest band, since no source names a month. Turmeric gives no month for sowing indoors. Where you see a blank, use the crop’s own page and your local extension office.

Next steps

Pick a crop from the calendar, open its page and read its “what the sources disagree on” table. If you want to see how fast each crop moves from planting to harvest, read our post on the fastest growing vegetables. If it is fall, see what to plant in November.