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Zone Guides6 min readMarch 6, 2026
Zone 6b Planting Guide 2026 | St. Louis, Nashville, Lexington Garden Calendar
Complete planting guide for USDA Zone 6b (St. Louis, Nashville, Lexington). Get exact 2026 planting dates, frost dates, and best varieties for zone 6b gardens.
USDA Hardiness Zone 6b Quick Facts
- Minimum Temperature: -5°F to 0°F (-20.6°C to -17.8°C)
- Average Last Frost: March 25 - April 10 (April 3 average)
- Average First Fall Frost: October 20 - November 5
- Growing Season: 170-200 days
- Best Planting Window: April 10-25 for warm-season crops
Major Cities in Zone 6b
Primary Cities: St. Louis, MO • Nashville, TN • Lexington, KY • Tulsa, OK • Wichita, KS • Evansville, IN
Also includes: Parts of Missouri, Tennessee, Kentucky, Oklahoma, Kansas, southern Indiana, and southern Illinois
Get Your Exact Zone 6b Planting Dates
2026 Zone 6b Planting Calendar
February - Early Indoor Starting
| Crop | Start Date | Transplant Date | Notes |
|---|---|---|---|
| Tomatoes | Feb 20 - March 10 | April 15-30 | Wide variety selection works here |
| Peppers | Feb 15 - March 5 | April 20 - May 5 | Even superhots are feasible |
| Eggplant | Feb 25 - March 10 | April 25 - May 5 | Needs warm soil (65°F+) |
| Herbs (Basil) | March 5-20 | April 20 - May 5 | Wait until nights stay above 50°F |
March - Cool Season Crops
| Crop | Direct Sow Date | Harvest | Notes |
|---|---|---|---|
| Peas | March 10-25 | May-June | One of the first crops to go in |
| Lettuce | March 15 - April 5 | May-June | Succession plant every 2 weeks |
| Spinach | March 10-25 | May-June | Sow early — bolts in heat |
| Radishes | March 15 - April 5 | April-May | Quick 25-day harvest |
| Carrots | March 20 - April 15 | June-August | Deep loose soil preferred |
April-May - Warm Season Planting
| Crop | Plant Date | Harvest Start | Notes |
|---|---|---|---|
| Beans (Bush) | April 20 - May 15 | June-August | Direct sow in warm soil |
| Corn | April 25 - May 15 | July-September | Full-season varieties work well |
| Squash (Summer) | April 20 - May 10 | June-September | Long harvest window |
| Cucumbers | April 20 - May 10 | June-September | Trellis for best results |
| Melons | May 1-15 | August-September | Plenty of heat for cantaloupes |
Best Varieties for Zone 6b
Tomatoes - Excellent Range
- Better Boy (72 days): Classic slicer, heavy producer
- Cherokee Purple (80 days): Rich heirloom flavor
- San Marzano (80 days): Best paste tomato
- Brandywine (90 days): Enough season for this long-season heirloom
- Cherry tomatoes: Sun Gold, Super Sweet 100, Black Cherry
Peppers - Full Range Available
- Sweet: California Wonder, Lunchbox, Giant Marconi
- Mild Hot: Poblano, Anaheim, Shishito
- Medium Hot: Jalapeño, Serrano, Cayenne
- Superhot: Habanero, Ghost Pepper (start indoors by Feb 1)
Cool Season Stars
- Lettuce: Buttercrunch, Romaine, Salanova mixes
- Spinach: Bloomsdale, Tyee, Corvair
- Peas: Sugar Snap, Snow Peas, Cascadia
- Carrots: Nantes, Danvers, Bolero
Zone 6b Frost Information
Critical Frost Dates for 2026
- Last Spring Frost: April 3 (average) — Range: March 25 - April 10
- Safe Planting Date: April 10-20 (add 1 week for safety)
- First Fall Frost: October 28 (average) — Range: October 20 - November 5
- Latest Recorded Spring Frost: April 22 (St. Louis area)
2026 Climate Considerations for Zone 6b
- Warm Springs: Zone 6b often gets early warm spells — resist the urge to plant too early
- Summer Heat: July-August regularly hits 95°F+ — heat-tolerant varieties recommended
- Humidity: Higher humidity east of the Mississippi increases disease pressure
- Long Fall: Extended mild fall allows late-season succession planting
Frost Protection Strategies
- Row Covers: Light fabric adds 4-6°F, good for early transplants
- Hardening Off: Zone 6b springs are changeable — take a full 7-10 days
- Raised Beds: Warm 1-2 weeks earlier than in-ground
- Season Extension: Low tunnels can push the fall harvest into November
Zone 6b Success Tips
Soil and Site Preparation
- Soil Test: Missouri and Tennessee soils range widely — test before amending
- Drainage: Clay soils are common in the mid-South — raised beds help
- pH: Many zone 6b soils are slightly acidic (6.0-6.5) — ideal for most vegetables
- Organic Matter: Add 2-3 inches of compost annually
Season Extension Techniques
- Start seeds indoors: 8-10 weeks before last frost for warm-season crops
- Fall planting: Zone 6b has a long enough fall for second plantings of lettuce, spinach, kale, and beets in August
- Succession planting: Stagger beans, lettuce, and radishes every 2-3 weeks
- Winter greens: Cold frames and low tunnels keep spinach and kale growing into December
Common Zone 6b Mistakes
- Planting too early after a warm spell: March warmth doesn't mean the last frost has passed
- Ignoring summer heat: Lettuce and spinach bolt fast — plan for shade cloth or heat-tolerant varieties
- Skipping fall gardens: The long zone 6b fall is a huge opportunity most gardeners miss
- Overwatering clay soil: Leads to root rot — water deeply but less frequently
Ready to Master Zone 6b Gardening?
→ Get Your Personalized Zone 6b Calendar
Exact dates, variety recommendations, and frost alerts for your specific location
Monthly Zone 6b Garden Tasks
February
- Start pepper and eggplant seeds indoors
- Order seeds and plan garden layout
- Prune dormant fruit trees and berry bushes
March
- Start tomato seeds indoors
- Direct sow peas, lettuce, spinach, radishes outdoors
- Prepare beds with compost
- Set up trellises for peas
April
- Transplant tomatoes, peppers, eggplant after last frost
- Direct sow beans, corn, squash
- Continue succession planting cool-season crops
- Mulch around transplants
May
- Plant melons, sweet potatoes, and okra
- Side-dress established plants with compost
- Install drip irrigation before summer heat
- Monitor for early pest pressure
Related Zone Guides
- Zone 6a Planting Guide
- Zone 7a Planting Guide
- Complete Spring Planting Calendar
- Tomato Planting by Zone
Last updated: March 6, 2026 | Zone 6b data based on USDA Plant Hardiness Zone Map 2023 and NOAA climate normals