About the Planting Schedule Calculator
This planting schedule calculator builds a vegetable planting calendar from your two frost dates. Enter your average last spring frost and first fall frost, choose a crop, and it gives the date to start seeds indoors (if the crop is usually transplanted), the date to plant out or direct sow, the expected first harvest and the latest date to plant again for a fall crop. A table lays out the same dates for 20 common vegetables.
It is meant for home and allotment gardeners planning a whole season at once — from peas and spinach sown weeks before the last frost to tomatoes, squash and corn planted once frost danger has passed. It also shows how many frost-free days your season has so you can choose varieties that will mature in time.
Timings are typical extension and seed-company guidance; days to maturity vary by variety, so check the packet. Frost dates are averages — there is still a real chance of a later spring frost — so keep frost cloth handy and wait for warm soil before planting tender crops.
How to use the planting schedule calculator
- 1Look up your average last spring and first fall frost dates.
- 2Enter both dates and choose a crop.
- 3Read the start-indoors, plant-out and harvest dates for that crop.
- 4Use the table to schedule every vegetable in your plan.
- 5Check the fall planting date to fit in a second crop.
Formula and method
Each crop has a typical offset from the last spring frost: hardy crops such as peas, spinach and onions go in several weeks before it, while frost-tender crops such as tomatoes, beans and squash wait until one to two weeks after. Transplanted crops are started indoors a set number of weeks before planting out.
The first harvest date adds the typical days to maturity (DTM) from transplanting or sowing. For a fall crop, the calculator counts back from the first fall frost by the days to maturity plus a 14-day "fall factor", a common allowance because plants grow more slowly as days shorten and cool.
- DTM
- Days to maturity from transplanting or direct sowing
- Weeks offset
- Weeks before (−) or after (+) last frost to plant out
- 14
- Fall factor — extra days for slower late-season growth
Worked examples
Tomatoes with an April 15 last frost
Tomatoes go out a week after the April 15 frost date, on April 22, after 8 weeks indoors from February 25. With 70 days to maturity the first fruit comes around July 1. For a fall crop, plant by October 15 − 84 days = July 23.
Peas with a March 30 last frost
Peas are direct sown about 5 weeks before the last frost — February 23. After 60 days they are ready around April 24. A fall crop should be sown by November 5 − 74 days = August 23.
Peppers in a short northern season
Peppers are transplanted two weeks after the May 25 frost date, on June 8, so seeds start 10 weeks earlier on March 30. First peppers arrive around August 17, leaving about a month before the September 15 frost.
Frequently asked questions
When should I plant vegetables after the last frost?+
Frost-tender crops such as tomatoes, peppers, beans, squash and corn are usually planted one to two weeks after the average last frost, once soil is warm. Hardy crops like peas, spinach, lettuce and onions can go in two to six weeks before it.
How do I find my frost dates?+
Your local cooperative extension service, national weather service climate data or a frost-date lookup by ZIP code gives average last spring and first fall frost dates. Remember they are averages, with roughly a 50% chance of frost on or after the spring date.
How far back do I start seeds indoors?+
Peppers and eggplant need about 8–10 weeks before transplanting, tomatoes 6–8 weeks, broccoli and cabbage 4–6 weeks, and fast crops like cucumbers and squash only 3–4 weeks, if they are started indoors at all.
What is the fall factor in garden planning?+
The fall factor is about 14 extra days added to a crop’s days to maturity when planning fall plantings, because cooler temperatures and shorter days slow growth late in the season compared with spring and summer.
Can I plant cool-season crops for fall?+
Yes — broccoli, kale, cabbage, carrots, beets, lettuce and spinach often taste better maturing in cool fall weather, and many survive light frosts. Count back from your first fall frost to time the sowing.