When to plant Cucumber in Knox County County,
The best window to plant Cucumber in Knox County County, is April 24–May 15, when soil warms to 50°F. Last frost typically hits April 17; first frost October 15.
When to Plant Cucumber in Knox County, IL
Your June gardening checklist
A quick June briefing for Knox County, Illinois gardeners — what's urgent, what's next, and what can wait.
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Harvest cucumber as they ripen
Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.
July will be here before you know it — start on
- First harvests: cucumber
Cucumbers are a warm-season vine crop available in slicing and pickling varieties. They are prolific producers when given warmth, moisture, and a trellis to climb.
Knox County, Illinois is in USDA Zone 5b. The average last spring frost is April 17 and the first fall frost is October 15, giving you a growing season of approximately 181 days.
At an elevation of 1,301 feet, Knox County receives approximately 33.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Cucumber to ensure they mature before fall.
Knox County Soil Profile
Soil Type
Silt Loam
Soil pH
6-6.8
Drainage
Well Drained
Cucumber 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 Knox County
How your county's soil matches Cucumber's growing requirements.
Soil pH
Your soil pH (6.0–6.8) is within Cucumber's preferred range (6.0–7.0).
Soil Texture
The silt loam soil in Knox County is excellent for Cucumber — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.5%) — Cucumber will thrive.
How to Plant Cucumber
Succession Planting Cucumber
Sow every 5.7 weeks. Last sowing by Aug 06 to harvest before frost.
Cucumber Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Cucumber
Cucumber 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 | Cucumber Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.4" | 0" | ❄️ Dormant |
| Apr | 6.5" | 3.4" | 3.1" | 💧 Light watering |
| May | 6.5" | 3.9" | 2.6" | 💧 Light watering |
| Jun | 6.5" | 3.6" | 2.9" | 💧 Light watering |
| Jul | 6.5" | 4.1" | 2.4" | 💧 Light watering |
| Aug | 6.5" | 3.5" | 3" | 💧 Light watering |
| Sep | 6.5" | 2.6" | 3.9" | 🚿 Regular watering |
| Oct | 6.5" | 2.7" | 3.8" | 🚿 Regular watering |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 1.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Knox County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Cucumber 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.
Cucumber Planting Timeline — Knox County, IL
Cucumber Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 13 | Mar 13 – Mar 27 |
| Transplant Outdoors | May 1 | May 1 – May 15 |
| Direct Sow | April 24 | Apr 24 – May 15 |
| Harvest | June 26 | Jun 26 – Aug 21 |
Plant 0.5" deep · 24" apart · Rows 48" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.5"/week · 2-3 times/week
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 6–7 · Your soil: ideal
🗺️ USDA Zone
Zone 5b
📆 Growing Season
181 days in Knox County
Growing Tips for Cucumber in Knox County
Direct sow Cucumber outdoors after April 17 in Knox County when soil has warmed and frost danger has passed.
Common pests for Cucumber in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow after last frost or start indoors 3 weeks early. Provide a trellis for vining types to save space and improve air circulation. Harvest frequently to encourage production.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Cucumber in Other Locations
Frequently Asked Questions
When should I plant Cucumber in Knox County, IL?
Knox County is in Zone 5b with an average last frost of April 17. Plan your Cucumber planting based on this frost date — see the calendar above for exact timing.
What planting zone is Knox County, IL?
Knox County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 17 and first fall frost is October 15.
When should I plant Cucumber in Knox County, ?
In Knox County, , plant Cucumber after the last frost (around April 17) and before the first frost (around October 15). Best results when soil holds above 50°F.
What growing zone is Knox County, for Cucumber?
Knox County sits in USDA Zone 5b. Cucumber grows reliably in zones 3a through 11b, so it's a good fit here.
Can Cucumber grow in Knox County's climate?
Yes — Cucumber grows well in Knox County's temperate climate. Knox County averages a 181-day frost-free season, with last frost around April 17 and first frost around October 15.
Your Knox County Garden Planner — Free
A 22-page printable planner built for Knox 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.