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When to plant Sunchoke in Compton, MD

Compton sits in cold Zone 8a. Plant Sunchoke April 19–May 3 for the single annual harvest; the November 4 first frost closes the window.

When to Plant Sunchoke in Compton, MD

St. Mary's County, Maryland Zone 8a June

June to-do list for St. Mary's County, Maryland

Your garden in St. Mary's County, Maryland is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost April 5
Avg. first frost November 4
Soil temp (4") 79°F
Watering Low
Pest pressure High
Daylight 14.6 hrs

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

Compton, Maryland is in USDA Zone 8a. The average last spring frost is April 5 and the first fall frost is November 4, giving you a growing season of approximately 213 days.

At an elevation of 156 feet, St. Mary's County receives approximately 41.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 92°F, providing good warmth for Sunchoke during the growing season.

Compton, MD (Zone 8a) Long season
213 days
Last Spring Frost April 5
213 growing days
First Fall Frost November 4

Compton Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.9

Drainage

Well Drained

Sunchoke Planting Risk Windows

Early Start (70% safe) ✓ Fits season (34 days to spare)
Transplant: Apr 11 🍅 Harvest: Aug 1 – Sep 26
Recommended (50%) ✓ Fits season (31 days to spare)
Transplant: Apr 19 🍅 Harvest: Aug 9 – Oct 4
Safe Start (90%) ✓ Fits season (44 days to spare)
Transplant: May 10 🍅 Harvest: Aug 30 – Oct 25

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 Compton

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

Soil pH

Your soil pH (5.5–6.9) overlaps with Sunchoke's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.0%). Annual compost additions will help Sunchoke.

How to Plant Sunchoke

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

Sunchoke 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 344 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 3.1" 0" ❄️ Dormant
Feb 2.6" 0" ❄️ Dormant
Mar 3.3" 0" ❄️ Dormant
Apr 4.3" 3.3" 1" 💧 Light watering
May 4.3" 3.9" 0.4" 💧 Light watering
Jun 4.3" 4.3" 0" ✅ Rainfall sufficient
Jul 4.3" 4" 0.3" 💧 Light watering
Aug 4.3" 4.3" 0" ✅ Rainfall sufficient
Sep 4.3" 3.6" 0.7" 💧 Light watering
Oct 4.3" 3.4" 0.9" 💧 Light watering
Nov 4.3" 2.7" 1.6" 💧 Light watering
Dec 2.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Nov in St. Mary's 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 ~2,470 GDD — county provides 4,047 GDD Excellent fit

Sunchoke Planting Timeline — Compton, MD

Sunchoke Planting Calendar

Activity When Date Range
Transplant Outdoors April 19 Apr 19 – May 3
Harvest August 9 Aug 9 – Oct 4

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

Month-by-Month Timeline

MonthActivities
January
February
March
April Transplant Outdoors
May Transplant Outdoors
June
July
August Harvest
September Harvest
October Harvest
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 8a

📆 Growing Season

213 days in St. Mary's County

Growing Tips for Sunchoke in Compton

Direct sow Sunchoke outdoors after April 05 in St. Mary's 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 →

When should I plant Sunchoke in Compton, MD?

In Compton, MD, plant Sunchoke after the last frost (around April 5) and before the first frost (around November 4). Best results when soil holds above 50°F.

What growing zone is Compton, MD for Sunchoke?

Compton sits in USDA Zone 8a. Sunchoke grows reliably in zones 3a through 9b, so it's a good fit here.

Can Sunchoke grow in Compton's climate?

Yes — Sunchoke grows well in Compton's temperate climate. Compton averages a 213-day frost-free season, with last frost around April 5 and first frost around November 4.

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Your St. Mary's County Garden Planner — Free

A 22-page printable planner built for St. Mary's 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.

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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 St. Mary's County, MD. Local conditions may vary. Last updated: June 2026.