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When to plant Leeks in Compton, MD

The best window to plant Leeks in Compton, is March 22–April 12, when soil warms to 50°F. Last frost typically hits April 5; first frost November 4. A second sowing from August 26 to September 9 extends the harvest into fall.

When to Plant Leeks in Compton, MD

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

What to do in June

A quick June briefing for St. Mary's County, Maryland gardeners — what's urgent, what's next, and what can wait.

Avg. last frost April 5
Avg. first frost November 4
Soil temp (4") 79°F
Watering Low
Pest pressure High
Daylight 14.6 hrs
Before July arrives, get these ready
  • First harvests: leeks

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Leeks are a mild, sweet allium that produces long white shanks. They are more refined than onions and are a key ingredient in soups, stews, and gratins.

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 Leeks 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

Leeks Planting Risk Windows

Early Start (70% safe) ✓ Fits season (48 days to spare)
Start indoors: Feb 21 Transplant: Mar 28 🍅 Harvest: Jun 27 – Sep 12
Recommended (50%) ✓ Fits season (45 days to spare)
Start indoors: Mar 1 Transplant: Apr 5 🍅 Harvest: Jul 5 – Sep 20
Safe Start (90%) ✓ Fits season (58 days to spare)
Start indoors: Mar 22 Transplant: Apr 26 🍅 Harvest: Jul 26 – Oct 11

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 Leeks's growing requirements.

Soil pH

Your soil pH (5.5–6.9) overlaps with Leeks's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

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

How to Plant Leeks

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Leeks Water Budget

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

Monthly Watering Guide for Leeks

Leeks needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Leeks Needs Rainfall You Supplement Action
Jan 3.1" 0" ❄️ Dormant
Feb 2.6" 0" ❄️ Dormant
Mar 3.3" 0" ❄️ Dormant
Apr 3.5" 3.3" 0.2" 💧 Light watering
May 3.5" 3.9" 0" ✅ Rainfall sufficient
Jun 3.5" 4.3" 0" ✅ Rainfall sufficient
Jul 3.5" 4" 0" ✅ Rainfall sufficient
Aug 3.5" 4.3" 0" ✅ Rainfall sufficient
Sep 3.5" 3.6" 0" ✅ Rainfall sufficient
Oct 3.5" 3.4" 0.1" 💧 Light watering
Nov 3.5" 2.7" 0.8" 💧 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.

Leeks 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.

Leeks needs ~2,280 GDD — county provides 4,047 GDD Excellent fit

Leeks Planting Timeline — Compton, MD

Leeks Planting Calendar

Activity When Date Range
Start Indoors March 1 Mar 1 – Mar 15
Transplant Outdoors April 5 Apr 5 – Apr 19
Direct Sow March 22 Mar 22 – Apr 12
Harvest July 5 Jul 5 – Sep 20
Fall Sowing August 26 Aug 26 – Sep 9

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow
May
June
July Harvest
August Fall Sowing Harvest
September Fall Sowing Harvest
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · Natural rainfall sufficient

📅 Days to Maturity

90–150 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 8a

📆 Growing Season

213 days in St. Mary's County

Growing Tips for Leeks in Compton

Direct sow Leeks outdoors after April 05 in St. Mary's County when soil has warmed and frost danger has passed.

Common pests for Leeks in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 10-12 weeks before last frost. Transplant into trenches and hill soil around stems as they grow to increase the white portion. Harvest as needed.

Companion Planting

Good Companions

Avoid Planting Near

  • Peas
  • Green Beans

Check more plant combinations with our Companion Planting Checker →

When should I plant Leeks in Compton, MD?

In Compton, MD, plant Leeks 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 Leeks?

Compton sits in USDA Zone 8a. Leeks grows reliably in zones 3a through 10b, so it's a good fit here.

Can Leeks grow in Compton's climate?

Yes — Leeks 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.

🌱

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.