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When to Plant Sunchoke in Cross County, AR

Sunchokes (Jerusalem artichokes) are a native sunflower relative grown for their knobby, nutty-flavored tubers. They are extremely productive and nearly impossible to eradicate.

Cross County, Arkansas is in USDA Zone 7b. The average last spring frost is March 19 and the first fall frost is November 7, giving you a growing season of approximately 233 days.

At an elevation of 531 feet, Cross County receives approximately 53.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89ยฐF, providing good warmth for Sunchoke during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sunchoke root diseases.

Cross County, AR (Zone 7b) Long season
233 days
Last Spring Frost March 19
233 growing days
First Fall Frost November 7

Cross County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (52 days to spare)
Transplant: Mar 26 🍅 Harvest: Jul 16 – Sep 10
Recommended (50%) ✓ Fits season (51 days to spare)
Transplant: Apr 2 🍅 Harvest: Jul 23 – Sep 17
Safe Start (90%) ✓ Fits season (50 days to spare)
Transplant: Apr 22 🍅 Harvest: Aug 12 – Oct 7

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 Cross County

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

Soil pH

Your soil pH (5.7โ€“6.7) overlaps with Sunchoke's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Sunchoke.

Organic Matter

Organic matter is moderate (3.1%). Annual compost additions will help Sunchoke.

How to Plant Sunchoke

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Sunchoke

Sunchoke needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Sunchoke Needs Rainfall You Supplement Action
Jan โ€” 5" 0" โ„๏ธ Dormant
Feb โ€” 4" 0" โ„๏ธ Dormant
Mar 4.3" 5.5" 0" โœ… Rainfall sufficient
Apr 4.3" 4.7" 0" โœ… Rainfall sufficient
May 4.3" 3.9" 0.4" ๐Ÿ’ง Light watering
Jun 4.3" 5.3" 0" โœ… Rainfall sufficient
Jul 4.3" 5.5" 0" โœ… Rainfall sufficient
Aug 4.3" 4.5" 0" โœ… Rainfall sufficient
Sep 4.3" 3.5" 0.8" ๐Ÿ’ง Light watering
Oct 4.3" 3" 1.3" ๐Ÿ’ง Light watering
Nov 4.3" 4.1" 0.2" ๐Ÿ’ง Light watering
Dec โ€” 4.4" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Cross County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Sunchoke 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" โ€” every day above 50ยฐF 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.

Sunchoke needs ~2,178 GDD — county provides 3,902 GDD Excellent fit

Sunchoke Planting Timeline โ€” Cross County, AR

Sunchoke Planting Calendar

Activity When Date Range
Transplant Outdoors April 2 Apr 2 โ€“ Apr 16
Harvest July 23 Jul 23 โ€“ Sep 17

Plant 1" deep ยท 30" apart ยท Rows 42" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Transplant Outdoors
May โ€”
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

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

110โ€“150 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

233 days in Cross County

Growing Tips for Sunchoke in Cross County

Direct sow Sunchoke outdoors after March 19 in Cross County when soil has warmed and frost danger has passed.

Common pests for Sunchoke in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Plant tubers 4 inches deep in early spring. Contain plants with barriers as they spread aggressively. Harvest after frost or leave in ground and dig as needed through winter.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sunchoke in Cross County, AR?

Cross County is in Zone 7b with an average last frost of March 19. Plan your Sunchoke planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Cross County, AR?

Cross County, Arkansas is in USDA Hardiness Zone 7b. The average last spring frost is March 19 and first fall frost is November 7.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Cross County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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