Seasonal Planting Calendar: What to Plant and When
Timing is the difference between a thriving garden and a disappointing one. Plant tomatoes too early and a late frost kills them. Plant spring bulbs too late and they do not have time to root before winter. Plant cool-season vegetables in summer heat and they bolt immediately. Every plant has an optimal planting window determined by your local frost dates and the plant's temperature preferences. This guide organizes the planting year into seasonal windows and tells you what to plant in each one, based on your last and first frost dates.
Understanding Frost Dates
Your last spring frost date and first fall frost date define your growing season. These dates are averages — your actual frost-free window varies by several weeks each year. Last frost dates range from February in the deep South to late May in northern states and high elevations. First fall frost dates range from September in northern areas to December in the South.
Use frost dates as the anchor for all planting decisions. Seed packets and plant tags specify timing relative to the last frost date: "start indoors 6-8 weeks before last frost," "direct sow after all danger of frost," or "plant in early fall, 8 weeks before first frost." Your local cooperative extension office provides frost dates specific to your county.
Early Spring: 6-8 Weeks Before Last Frost
Start warm-season vegetable seeds indoors: tomatoes, peppers, eggplant, and herbs like basil. These need 6 to 8 weeks of indoor growth before transplanting outdoors after the last frost. Use seed starting mix, keep temperatures at 65 to 75 degrees F, and provide 12 to 16 hours of light daily.
Outdoors, this is the window for planting bare-root trees, shrubs, and fruit trees while they are still dormant. Cool-season vegetables that tolerate light frost — peas, spinach, lettuce, radishes, kale, and onion sets — can go directly into prepared garden beds 4 to 6 weeks before the last frost date.
- Start indoors: tomatoes, peppers, eggplant, basil
- Direct sow outdoors: peas, spinach, lettuce, radishes, kale
- Plant outdoors: bare-root trees, shrubs, fruit trees
- Landscape: divide perennials, prune dormant shrubs
Late Spring: After Last Frost
After all danger of frost has passed, transplant warm-season seedlings outdoors: tomatoes, peppers, squash, cucumbers, and herbs. Harden off indoor-started seedlings by gradually exposing them to outdoor conditions over 7 to 10 days before transplanting.
This is also the primary window for planting warm-season annuals (marigolds, petunias, zinnias), installing sod, seeding warm-season grasses, and planting container gardens. Direct sow beans, corn, squash, and melons when soil temperature reaches 60 to 65 degrees F.
Late Summer to Early Fall: 8-10 Weeks Before First Frost
Fall is the second major planting season and arguably the best time for many landscape plants. Plant cool-season vegetables for a fall harvest: broccoli, cauliflower, Brussels sprouts, kale, lettuce, spinach, and carrots. Count backward from your first frost date to determine the planting window — most cool-season crops need 60 to 90 days to mature.
Fall is ideal for planting trees, shrubs, and perennials. Cooler temperatures reduce transplant stress, and autumn rains reduce watering needs while roots establish. Spring flowering bulbs (tulips, daffodils, crocus, hyacinth) must be planted in fall, 6 to 8 weeks before the ground freezes, to allow root development before winter dormancy.
Winter: Planning and Preparation
Winter is for planning. Review the previous season — what grew well, what failed, what spacing worked. Order seeds in January and February for the best selection. Test your soil (most extension services offer winter soil testing with fast turnaround) and amend based on results before spring planting.
In mild climates (zones 8-10), winter is an active growing season for cool-season vegetables. Plant garlic in late fall for harvest the following summer. In cold climates, apply winter mulch to perennial beds after the ground freezes to protect roots from freeze-thaw cycles. Prune deciduous trees while they are dormant for the best visibility of branch structure.
Frequently Asked Questions
When should I start seeds indoors?
Start most warm-season vegetables (tomatoes, peppers, eggplant) 6 to 8 weeks before your last frost date. Start slower-growing herbs and flowers 8 to 10 weeks before. Count backward from your last frost date to determine the start date. Too early and seedlings become leggy; too late and they are not ready for transplanting.
What vegetables can I plant in fall?
Cool-season crops planted 8 to 10 weeks before the first frost: broccoli, cauliflower, Brussels sprouts, kale, lettuce, spinach, radishes, and carrots. Many of these taste better after a light frost, which converts starches to sugars. Fall-planted garlic grows roots in autumn and produces full bulbs the following summer.
How do I find my frost dates?
Your local cooperative extension office provides frost dates specific to your county. Online tools like the USDA Plant Hardiness Zone Map and the Old Farmer's Almanac frost date calculator provide estimates based on zip code. Remember these are averages — actual frost dates vary by 2 to 3 weeks each year.
Can I plant trees in summer?
Container-grown trees can be planted in summer, but they require significantly more water and have higher failure rates than fall or spring plantings. Avoid planting bare-root trees in summer — they will likely die. If you must plant in summer, choose overcast or cool days, water deeply at planting, mulch heavily, and provide consistent irrigation for the first growing season.
What is the best time to plant perennials?
Fall is the best time in most climates. Cooler temperatures reduce stress, autumn rains provide moisture, and roots establish before winter. Spring is the second-best window. Spring-blooming perennials should be planted in fall; fall-blooming perennials can be planted in spring. Avoid planting in the heat of summer.