Blog

When to Plant Sunchoke in Cumberland County, NJ

Cumberland County, New Jersey Zone 7b May

What to do in May

Your garden in Cumberland County, New Jersey is working on a schedule, even when you're not. Here's where you should be this May.

Avg. last frost March 28
Avg. first frost November 12
Soil temp (4") 70°F
Watering Low
Pest pressure Moderate
Daylight 14.2 hrs

Instant PDF download. No spam, unsubscribe any time.

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

Cumberland County, New Jersey is in USDA Zone 7b. The average last spring frost is March 28 and the first fall frost is November 12, giving you a growing season of approximately 229 days.

At an elevation of 425 feet, Cumberland County receives approximately 42 inches of rainfall annually with predominantly silt loam soil. Summer highs average 94°F, providing good warmth for Sunchoke during the growing season.

Cumberland County, NJ (Zone 7b) Long season
229 days
Last Spring Frost March 28
229 growing days
First Fall Frost November 12

Cumberland County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (47 days to spare)
Transplant: Apr 6 🍅 Harvest: Jul 27 – Sep 21
Recommended (50%) ✓ Fits season (47 days to spare)
Transplant: Apr 11 🍅 Harvest: Aug 1 – Sep 26
Safe Start (90%) ✓ Fits season (56 days to spare)
Transplant: Apr 23 🍅 Harvest: Aug 13 – Oct 8

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 Cumberland County

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

Soil pH

Your soil pH (5.2–6.8) overlaps with Sunchoke's range (6.0–7.5), though not a perfect match.

Soil Texture

The silt loam soil in Cumberland County is excellent for Sunchoke — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.7%). 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
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 468 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 3.4" 0" ❄️ Dormant
Feb 2.8" 0" ❄️ Dormant
Mar 4.3" 3.5" 0.8" 💧 Light watering
Apr 4.3" 3.4" 0.9" 💧 Light watering
May 4.3" 4.4" 0" ✅ Rainfall sufficient
Jun 4.3" 3.8" 0.5" 💧 Light watering
Jul 4.3" 4.1" 0.2" 💧 Light watering
Aug 4.3" 3.9" 0.4" 💧 Light watering
Sep 4.3" 3.3" 1" 💧 Light watering
Oct 4.3" 3.6" 0.7" 💧 Light watering
Nov 4.3" 3.1" 1.2" 💧 Light watering
Dec 2.9" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Cumberland County). Supplement amounts are based on average rainfall — 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" — 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.

Sunchoke needs ~2,665 GDD — county provides 4,694 GDD Excellent fit

Sunchoke Planting Timeline — Cumberland County, NJ

Sunchoke Planting Calendar

Activity When Date Range
Transplant Outdoors April 11 Apr 11 – Apr 25
Harvest August 1 Aug 1 – Sep 26

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

110–150 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 7b

📆 Growing Season

229 days in Cumberland County

Growing Tips for Sunchoke in Cumberland County

Direct sow Sunchoke outdoors after March 28 in Cumberland 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 Cumberland County, NJ?

Cumberland County is in Zone 7b with an average last frost of March 28. Plan your Sunchoke planting based on this frost date — see the calendar above for exact timing.

What planting zone is Cumberland County, NJ?

Cumberland County, New Jersey is in USDA Hardiness Zone 7b. The average last spring frost is March 28 and first fall frost is November 12.

🌱

Your Cumberland County Garden Planner — Free

A 24-page printable planner built for Cumberland County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.