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When to Plant Rue in McHenry County, IL

Rue is a bitter, aromatic perennial herb with bluish-green foliage used historically in medicine and as a pest deterrent. Handle with care as its sap can cause skin irritation.

McHenry County, Illinois is in USDA Zone 5a. The average last spring frost is April 18 and the first fall frost is October 20, giving you a growing season of approximately 185 days.

At an elevation of 640 feet, McHenry County receives approximately 39.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Rue to ensure they mature before fall.

McHenry County, IL (Zone 5a) Moderate season
185 days
Last Spring Frost April 18
185 growing days
First Fall Frost October 20

McHenry County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (41 days to spare)
Transplant: Apr 20 🍅 Harvest: Jun 29 – Aug 31
Recommended (50%) ✓ Fits season (45 days to spare)
Transplant: Apr 25 🍅 Harvest: Jul 4 – Sep 5
Safe Start (90%) ✓ Fits season (44 days to spare)
Transplant: May 11 🍅 Harvest: Jul 20 – Sep 21

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 McHenry County

How your county's soil matches Rue's growing requirements.

Soil pH

Your soil pH (5.9โ€“6.7) overlaps with Rue's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The silt loam soil in McHenry County is excellent for Rue โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.1%) โ€” Rue will thrive.

How to Plant Rue

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Rue

3
successive plantings in your 185-day season

Sow every 8 weeks. Last sowing by Jul 22 to harvest before frost.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Rue needs ~1,040 GDD — county provides 2,405 GDD Excellent fit

Rue Planting Timeline โ€” McHenry County, IL

Rue Planting Calendar

Activity When Date Range
Transplant Outdoors April 25 Apr 25 โ€“ May 9
Harvest July 4 Jul 4 โ€“ Sep 5

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Transplant Outdoors
May Transplant Outdoors
June โ€”
July Harvest
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

70โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 5a

๐Ÿ“† Growing Season

185 days in McHenry County

Growing Tips for Rue in McHenry County

Direct sow Rue outdoors after April 18 in McHenry County when soil has warmed and frost danger has passed.

General growing tips

Start seeds indoors or direct sow. Plant in well-drained soil. Wear gloves when handling as sap can cause phytophotodermatitis. Prune in early spring.

Companion Planting

Good Companions

Avoid Planting Near

  • Basil
  • Sage

Level Up Your Garden

Frequently Asked Questions

When should I plant Rue in McHenry County, IL?

McHenry County is in Zone 5a with an average last frost of April 18. Plan your Rue planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is McHenry County, IL?

McHenry County, Illinois is in USDA Hardiness Zone 5a. The average last spring frost is April 18 and first fall frost is October 20.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help McHenry County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for McHenry County, IL. Local conditions may vary. Last updated: April 2026.