DeKalb County, IL — Planting Guide
DeKalb County is in USDA Zone 5b. The average last spring frost is April 22 and the first fall frost is October 16, giving you a growing season of approximately 177 days.
At an elevation of 1,332 ft, DeKalb County receives approximately 34.3 in of rainfall annually. Summer highs average 87°F with winter lows around 10°F. The predominant soil type is Silt Loam.
🌡️ Zone
5b (-15°F to -10°F min)
❄️ Last Frost
April 22
🍂 First Frost
October 16
📅 Growing Season
177 days
⛰️ Elevation
1,332 ft
🌧️ Annual Rainfall
34.3 in
DeKalb County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Soil & Growing Conditions in DeKalb County
Soil Type
Silt Loam
Ideal for most crops — holds moisture and nutrients while draining well.
Watering Needs
Moderate rainfall (34.3 in.) — plan to water 1–2 times per week during the growing season.
Season Tips
177-day frost-free season
Start warm-season crops indoors and focus on short-season varieties. Cold frames extend your season by 3–4 weeks in fall.
Your Free Printable Garden Planner
Plan every bed, every planting, every harvest — in one place. This 22-page printable includes your zone's planting calendar, a month-by-month task list, a seed inventory tracker, a harvest log, and succession-planting charts. Built to print, write in, and actually use all season.
Recommended for Your Garden
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
Get instant, accurate soil pH readings to fine-tune your amendments.
Boost soil fertility and structure with rich, well-aged organic compost.
Monthly Planting Guide for DeKalb County
Gardening Guides & Resources
Helpful guides from The Ultimate Homestead to improve your garden in DeKalb County.
Frequently Asked Questions
What planting zone is DeKalb County, IL?
DeKalb County is in USDA Hardiness Zone 5b. This zone classification determines which perennial plants survive winter and sets the baseline for frost timing across the county.
When is the last frost in DeKalb County, IL?
Based on 30 years of NOAA weather station data, the median last spring frost in DeKalb County falls around April 22. Plan transplants and direct-sow dates relative to this date.
When is the first fall frost in DeKalb County, IL?
The median first fall frost in DeKalb County arrives around October 16. Harvest or protect frost-sensitive crops — tomatoes, peppers, basil, squash — before this date.
Your DeKalb County Garden Planner — Free
A 22-page printable planner built for DeKalb County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.
The Gardener's Encyclopedia to Companion Planting
The pairings that make vegetables, herbs, and flowers grow better — and the ones that quietly wreck a bed.
- Proven pairings for 200+ vegetables, herbs, flowers, and fruits
- Full seed-starting + planting schedule with timing and spacing
- Bonus: square-foot gardening guide + printable seasonal planners
Seed Saving & Storage Guide
Most saved seeds go bad before next season. This shows exactly when to pick, how to dry, and where to store seeds from 200 plants so yours don't.
- 200 plants, step-by-step: life cycle, pollination type, isolation
- Exact temperature + humidity ranges that keep seeds viable
- Bonus: searchable Google Sheets tracker + custom GPT assistant
Composting Guide for Homesteaders
Turn kitchen scraps and yard waste into compost that actually feeds the garden — instead of a pile that smells, attracts pests, and never breaks down.
- 14 sections on composting methods, soil science, and troubleshooting
- The 7-step hot-compost system from start to finish
- Bonus tools: troubleshooting chart, safety guide, monitoring log