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When to plant Leeks in Paramount, CA

For Paramount, gardeners: plant Leeks March 13 through April 3 once soil reads 50°F. A second sowing from September 26 to October 10 extends the harvest into fall.

When to Plant Leeks in Paramount, CA

Leeks
Los Angeles County, California Zone 10b June

What to do in June

If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.

Avg. last frost April 3
Avg. first frost November 21
Soil temp (4") 86°F
Watering Critical
Pest pressure High
Daylight 14.3 hrs
  1. Survive, don't thrive

    June-August is endurance gardening. Keep okra, peppers, sweet potatoes, and southern peas alive. Harvest everything daily before the heat damages produce on the vine.

  2. Start fall tomato seeds indoors

    Yes, indoors — under lights or in AC. They'll be ready to transplant in August when temperatures briefly moderate.

  3. Add compost to empty beds

    Empty beds get a thick layer of compost + mulch to suppress weeds and feed the soil for fall planting.

July will be here before you know it — start on
  • 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.

Paramount, California is in USDA Zone 10b. The average last spring frost is April 3 and the first fall frost is November 21, giving you a growing season of approximately 232 days.

At an elevation of 1,315 feet, Los Angeles County receives approximately 12.9 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Leeks during the growing season. With low rainfall, drip irrigation is essential for growing Leeks successfully. Mulch heavily to conserve soil moisture.

Paramount, CA (Zone 10b) Long season
232 days
Last Spring Frost April 3
232 growing days
First Fall Frost November 21

Paramount Soil Profile

Soil Type

Loam

Soil pH

5.8-7.5

Drainage

Well Drained

Leeks Planting Risk Windows

Early Start (70% safe) ✓ Fits season (80 days to spare)
Start indoors: Feb 6 Transplant: Mar 6 🍅 Harvest: Jun 5 – Aug 21
Recommended (50%) ✓ Fits season (64 days to spare)
Start indoors: Mar 6 Transplant: Apr 3 🍅 Harvest: Jul 3 – Sep 18
Safe Start (90%) ✓ Fits season (28 days to spare)
Start indoors: Apr 30 Transplant: May 28 🍅 Harvest: Aug 27 – Nov 12

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 Paramount

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

Soil pH

Your soil pH (5.8–7.5) overlaps with Leeks's range (6.0–7.0), though not a perfect match.

Soil Texture

The loam soil in Los Angeles County is excellent for Leeks — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.1%). Annual compost additions will help Leeks.

How to Plant Leeks

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

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Leeks Water Budget

Plant needs
0.8″/week
Rainfall provides
0.2″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 1,404 gal / 100 sq ft
Drought risk

Water stress score is 10/10 — consider drought-tolerant varieties and mulching

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 2.4" 0" ❄️ Dormant
Feb 2.5" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 3.5" 1.2" 2.3" 🚿 Regular watering
May 3.5" 0.4" 3.1" 🚿 Regular watering
Jun 3.5" 0.1" 3.4" 🚿 Regular watering
Jul 3.5" 0" 3.5" 🚿 Regular watering
Aug 3.5" 0" 3.5" 🚿 Regular watering
Sep 3.5" 0.2" 3.3" 🚿 Regular watering
Oct 3.5" 0.6" 2.9" 🚿 Regular watering
Nov 3.5" 1.3" 2.2" 🚿 Regular watering
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Nov in Los Angeles 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 ~1,830 GDD — county provides 3,538 GDD Excellent fit

Leeks Planting Timeline — Paramount, CA

Leeks Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 – Mar 20
Transplant Outdoors April 3 Apr 3 – Apr 17
Direct Sow March 13 Mar 13 – Apr 3
Harvest July 3 Jul 3 – Sep 18
Fall Sowing September 26 Sep 26 – Oct 10

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 Harvest
September Fall Sowing Harvest
October Fall Sowing
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · 1-2 times/week

📅 Days to Maturity

90–150 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 10b

📆 Growing Season

232 days in Los Angeles County

Growing Tips for Leeks in Paramount

Direct sow Leeks outdoors after April 03 in Los Angeles 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 Paramount, CA?

In Paramount, CA, plant Leeks after the last frost (around April 3) and before the first frost (around November 21). Best results when soil holds above 50°F.

What growing zone is Paramount, CA for Leeks?

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

Can Leeks grow in Paramount's climate?

Yes — Leeks grows well in Paramount's temperate climate. Paramount averages a 232-day frost-free season, with last frost around April 3 and first frost around November 21.

🌱

Your Los Angeles County Garden Planner — Free

A 22-page printable planner built for Los Angeles County (Zone 10b). 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 Los Angeles County, CA. Local conditions may vary. Last updated: June 2026.