When to Plant a Garden: A Simple Guide for Every Season

Why Timing Matters More Than the Calendar

It's tempting to plant the first warm weekend of the year, but a 70-degree day in March doesn't mean frost is done, and one cold snap can wipe out tender seedlings overnight.

The two dates that matter most are your average last frost date in spring and your average first frost date in fall. They're averages based on years of local weather data, not guarantees, but they're the most reliable starting point you have.

Soil temperature matters just as much as air temperature. Seeds and roots respond to what's happening a few inches underground, and in early spring the soil often lags several degrees behind the air.

How Do You Find Your Frost Dates and Hardiness Zone?

Look both up online by zip code: the USDA Plant Hardiness Zone Map gives your zone, and your local extension service or a frost-date lookup gives your average last and first frost dates. It takes a couple of minutes and shapes every planting decision this year.

Your hardiness zone tells you which perennials, shrubs and trees can survive your winters. Your frost dates tell you when it's safe to plant annuals, vegetables and seedlings.

For example, a gardener in zone 9 (much of Florida and coastal California) might see a last frost in February and a first frost in December, giving them a nearly year-round season. A gardener in zone 4 (parts of Minnesota or Maine) might not see a safe last frost until late May, with first frost arriving by mid-September.

Write both dates somewhere you'll actually see them, because nearly every timing rule below counts forward or backward from them:

When Should You Plant Vegetables in Spring?

Plant spring vegetables in two waves: cool-season crops 2-4 weeks before your last frost, then warm-season crops 1-2 weeks after it. Mixing up the two waves is one of the most common timing mistakes.

Lettuce, spinach, peas, radishes, kale and broccoli handle light frost and prefer cool soil, so they go in as soon as the soil can be worked. Raised beds help here, because they warm up and drain faster than in-ground soil; see our guide to building a raised garden bed if you're starting from scratch.

Tomatoes, peppers, cucumbers, squash, beans and melons are frost-sensitive and want soil at 60°F or higher, with nighttime temperatures reliably above 50°F. If you're not sure what to grow first, these easy vegetables for beginner raised beds are a forgiving place to start.

Flowering annuals like marigolds and zinnias follow the same warm-season timing as tomatoes; they're just as vulnerable to a late cold snap.

Summer: Keeping the Garden Productive Through the Heat

Summer isn't only for harvesting. It's also a planting window if you pick the right crops.

Fast-growing warm-season vegetables like bush beans, cucumbers and summer squash can still be direct-seeded in early summer for a second harvest before fall. Succession planting, sowing a new round of beans every 2-3 weeks, keeps the garden producing instead of peaking once and stalling.

Skip cool-season crops in peak heat. Lettuce and spinach sown in July heat tend to bolt (shoot up and turn bitter) quickly instead of producing a good harvest.

If your summers regularly hit 90°F or higher, treat midsummer as a holding pattern for new plantings and focus on deep watering and mulching instead.

Fall: The Planting Window Most Gardeners Skip

Fall is one of the best times to plant, with cooler air, still-warm soil and fewer pests working in your favor.

Count backward from your first frost date. Kale, spinach, carrots and lettuce can go back in 6-10 weeks before that date for a second harvest. Many of them taste sweeter after a light frost, as cold prompts the plant to convert starches into sugars.

Fall is also garlic season. Plant cloves roughly 2-6 weeks before the ground freezes so they root before winter and are ready to harvest the following summer.

For tulips, daffodils or crocuses next spring, this is the window to plant bulbs, generally once nighttime temperatures settle into the 40-50°F range.

Winter: What You Can Still Plant When It's Cold

In most of the country, winter isn't a vegetable planting season, but it isn't a dead season for the garden either.

In zones 8 and warmer, spinach, kale and certain lettuces can grow right through winter, sometimes with a row cover or cold frame on the coldest nights.

In colder zones, late winter is a good time to plant dormant bare-root trees and shrubs whenever the ground isn't frozen, so they establish roots before spring growth begins.

Winter is also the time to plan next year's layout, order seeds before popular varieties sell out, and test your soil so you can prepare your garden soil before spring planting begins.

When Should You Start Seeds Indoors?

Start warm-season seeds like tomatoes and peppers indoors about 6-8 weeks before your last frost date. That gives seedlings time to grow sturdy stems and a few sets of true leaves before they move outside.

Don't rush the move. Harden off seedlings by setting them outside for a few hours a day over about a week, gradually increasing sun exposure, before planting them in the ground. Skipping this step is one of the fastest ways to lose seedlings to sunscald or transplant shock.

Common Timing Mistakes That Set a Garden Back

Planting warm-season crops too early is the most common mistake. A few mild days convince people to plant tomatoes, and a frost a week later takes them out.

Ignoring soil temperature is another. Seeds sown into cold, wet soil often rot instead of germinating, even when the afternoons feel warm.

A third is following a planting calendar written for someone else's region. Advice built for zone 6 will be off for zone 9 or zone 3, so always adjust to your own frost dates.

Finally, skipping fall planting means missing one of the easiest harvests of the year, especially for cool-season crops that improve in cooler weather.