Seasonal Guide
Month-by-month guide to what to plant in spring — cool-season crops, warm-season timing, seed starting calendar, and zone-by-zone last frost dates.
Indoor Seed Starting + Earliest Cool-Season Outdoors
Start 6–8 weeks before last frost. Use grow lights (not just a window). Pot up when first true leaves appear.
Start 8–10 weeks before last frost — peppers are slow. Needs 75–80°F soil temp to germinate: use heat mat.
Start 10–12 weeks before transplanting outdoors. Long season crops — early indoor start essential for bulb size.
Start 6–8 weeks before last frost. Basil needs warmth (70°F+) to germinate — use heat mat.
Zones 7–9: direct sow outdoors under row cover. These crops germinate in soil temps as low as 35°F.
Garlic planted last fall emerges now — apply balanced fertilizer as green growth begins.
Cool-Season Outdoor Sowing Begins (Zones 5–9)
Start tomatoes now for northern climates with late last frost (May 15–June 1).
Start slow-growing annuals indoors: petunias, geraniums, snapdragons (10–12 weeks before last frost).
Start 8–10 weeks before last frost — same timing as peppers.
Direct sow peas as soon as soil can be worked — they're frost-hardy and actually prefer cool weather. Sow 1 in deep, 2 in apart.
Zones 5–9: direct sow outdoors. Thin to 4–6 in spacing. Can also transplant 6-pack starts from nursery.
Transplant hardened-off starts 4–6 weeks before last frost. They tolerate hard frosts once acclimated.
Direct sow root vegetables in loose, worked soil. Radishes 25 days; beets 55 days; carrots 70–80 days.
Plant 1-year crowns in prepared trench (12 in wide, 6–8 in deep): add compost, set crowns with roots spread, backfill 3 in. Don't harvest for 2 years.
Warm-Season Transplants Begin + Cool-Season in Full Swing
Start 3–4 weeks before last frost — these transplant poorly if rootbound; don't start too early.
Start basil now — it goes out with tomatoes after last frost. Needs warmth to thrive.
Transplant tomatoes outdoors — frost risk has passed. Bury stem up to first leaves for stronger root system.
Zones 5+: plant seed potatoes in trenches 4 in deep, 12 in apart as soon as soil is workable.
Plant bare-root strawberries in April — crown at soil surface, roots spread. First year: remove flowers so plants put energy into runners.
Pansies, snapdragons, lobelia: can go out 2–4 weeks before last frost. These tolerate light frost.
Second best planting time (fall is best): spring-planted trees and shrubs establish well. Plant before heat arrives.
After Last Frost: Warm-Season Planting in Full Swing
Last frost date passed: transplant all nightshades outdoors. Harden off for 7–10 days before transplanting (progressively increase outdoor exposure).
Direct sow or transplant after last frost. Cucumbers prefer direct sow in warm soil (65°F+). One zucchini plant per household.
Direct sow in warm soil 60°F+. Beans don't like transplanting. Sow 1 in deep, 3–4 in apart. Germination 7–10 days.
Need 90–120 days of warm weather: start outdoors in zones 5–6 immediately after last frost to get full season.
All tender annuals: impatiens, begonias, coleus, basil — they die below 50°F. After last frost only. Buy transplants or direct-sow zinnias, cosmos, sunflowers.
Plant dahlia tubers after last frost in warm soil. Do NOT water until you see sprouts (2–3 weeks): prevents rot.
Find your zone to know exactly when to start seeds and transplant outdoors.
| Zone | Last Frost Date | Example States | Indoor Seed Start | Main Planting |
|---|---|---|---|---|
| Zone 3 | May 15–June 1 | Northern MN, ND, WI, MT (high elevation) | Late Feb–Early March | June |
| Zone 4 | May 1–May 15 | MN, WI, IA, upstate NY, northern NE | Mid-Feb to March | Mid-May |
| Zone 5 | April 15–May 1 | IL, IN, OH, PA, NY metro, MA, CT | Early–Mid February | Early May |
| Zone 6 | April 1–April 15 | MD, VA, KY, MO, KS, NM, OR coast | Late January–February | Late April |
| Zone 7 | March 15–April 1 | NC, TN, AR, OK, TX north, WA west | January | Early April |
| Zone 8 | February 15–March 15 | AL, MS, GA, SC, TX coast, OR/WA coast | December–January | March |
| Zone 9 | January 15–February 15 | FL north, CA central valley, LA, TX south | Nov–December | February |
| Zone 10–11 | None or rare | FL south, Hawaii, S. California coast | Year-round | Year-round (heat matters) |
Cool-season crops (lettuce, peas, kale, spinach, broccoli, radishes) thrive in 40–65°F temperatures and tolerate frost. They can go outdoors 4–6 weeks before your last frost date. Warm-season crops (tomatoes, peppers, cucumbers, squash, beans, basil) die below 50°F and require warm soil. Plant them after last frost when soil reaches 60–65°F.
Hardening off is gradually acclimating indoor-grown seedlings to outdoor conditions over 7–10 days: Start with 1 hour outside in shade, then 2 hours, then full day shade, then introduce sun progressively. Skipping hardening off causes transplant shock — leaves scorch and plants may die. Takes 7–10 days but is essential.
Yes — Wall-O-Waters (tomato protectors) allow tomatoes to go out 4–6 weeks before last frost in zones 5–7. Hoop houses and cold frames provide 10–15°F of frost protection. Row cover fabric provides 4–6°F of protection. These tools significantly extend your season in cooler climates.
The first things to plant in spring: peas (as soon as soil can be worked — they need cold), then spinach and lettuce under row cover, then kale and brassica transplants. These crops actually prefer cool weather. Don't be tempted to rush warm-season crops (tomatoes, peppers) — cold soil and air stunt them and they never fully recover.
The squeeze test: grab a handful of soil and squeeze. If it forms a tight ball that doesn't crumble when tapped, it's too wet (tilling damages soil structure). If it crumbles easily when tapped, it's ready. Also measure soil temp: cool-season crops need 40°F+ soil; warm-season crops need 60–65°F+ soil. Soil thermometers are $10–15 and worth it.
Planting too early — specifically putting tomatoes and peppers out before the soil warms to 65°F. Cold-stunted tomatoes end up smaller than plants put in 3 weeks later in warm soil. The second biggest mistake: not hardening off transplants, leading to transplant shock that sets plants back 2–3 weeks.
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