When to plant Corn in Johnson County, AR
In Johnson County, plant Corn in spring between April 2 and April 23, once soil temps hold above 50°F. Johnson County's last frost averages March 26, so most warm-season crops establish quickly once soil holds above 60°F. For a fall crop, sow between and — roughly 60–100 days before the first frost on November 3.
When to Plant Corn in Johnson County, AR
Your July gardening checklist
Your garden in Johnson County, Arkansas is working on a schedule, even when you're not. Here's where you should be this July.
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It's harvest week for corn
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
Corn is a warm-season grass grown for its sweet ears, which are best eaten soon after harvest. It is wind-pollinated and must be planted in blocks for good kernel fill.
Johnson County, Arkansas is in USDA Zone 8a. The average last spring frost is March 26 and the first fall frost is November 3, giving you a growing season of approximately 222 days.
At an elevation of 1,347 feet, Johnson County receives approximately 49.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Corn during the growing season.
Johnson County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-7
Drainage
Well Drained
Corn Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in Johnson County
How your county's soil matches Corn's growing requirements.
Soil pH
Your soil pH (5.3–7.0) overlaps with Corn's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Johnson County is excellent for Corn — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Corn.
How to Plant Corn
Succession Planting Corn
Sow every 6.9 weeks. Last sowing by Jul 26 to harvest before frost.
Corn Water Budget
Monthly Watering Guide for Corn
Corn needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.
| Month | Corn Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.8" | 0" | ❄️ Dormant |
| Feb | — | 3.8" | 0" | ❄️ Dormant |
| Mar | 6.5" | 4.7" | 1.8" | 💧 Light watering |
| Apr | 6.5" | 3.6" | 2.9" | 💧 Light watering |
| May | 6.5" | 4.1" | 2.4" | 💧 Light watering |
| Jun | 6.5" | 5" | 1.5" | 💧 Light watering |
| Jul | 6.5" | 4.6" | 1.9" | 💧 Light watering |
| Aug | 6.5" | 4.3" | 2.2" | 💧 Light watering |
| Sep | 6.5" | 4.1" | 2.4" | 💧 Light watering |
| Oct | 6.5" | 3.7" | 2.8" | 💧 Light watering |
| Nov | 6.5" | 4.2" | 2.3" | 💧 Light watering |
| Dec | — | 3.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Johnson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Corn Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Corn Planting Timeline — Johnson County, AR
Corn Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | April 2 | Apr 2 – Apr 23 |
| Harvest | June 4 | Jun 4 – Jul 30 |
Plant 1" deep · 12" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.5"/week · 1-2 times/week
📅 Days to Maturity
60–100 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 8a
📆 Growing Season
222 days in Johnson County
Growing Tips for Corn in Johnson County
Direct sow Corn outdoors after March 26 in Johnson County when soil has warmed and frost danger has passed.
Common pests for Corn in this region include corn earworm and corn borers. Use row covers early in the season and inspect plants weekly.
General growing tips
Plant in blocks of at least 4 rows rather than single rows for proper pollination. Direct sow after soil reaches 60F. Side-dress with nitrogen when plants are knee-high.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Corn in Other Locations
Frequently Asked Questions
When should I plant Corn in Johnson County, AR?
Johnson County is in Zone 8a with an average last frost of March 26. Plan your Corn planting based on this frost date — see the calendar above for exact timing.
What planting zone is Johnson County, AR?
Johnson County, Arkansas is in USDA Hardiness Zone 8a. The average last spring frost is March 26 and first fall frost is November 3.
When should I plant Corn in Johnson County, AR?
In Johnson County, AR, plant Corn after the last frost (around March 26) and before the first frost (around November 3). Best results when soil holds above 50°F.
What growing zone is Johnson County, AR for Corn?
Johnson County sits in USDA Zone 8a. Corn grows reliably in zones 3a through 11b, so it's a good fit here.
Can Corn grow in Johnson County's climate?
Yes — Corn grows well in Johnson County's temperate climate. Johnson County averages a 222-day frost-free season, with last frost around March 26 and first frost around November 3.
Your Johnson County Garden Planner — Free
A 22-page printable planner built for Johnson County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.