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When to Plant Leeks in Colorado County, TX

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.

Colorado County, Texas is in USDA Zone 8b. The average last spring frost is February 26 and the first fall frost is December 4, giving you a growing season of approximately 281 days.

At an elevation of 87 feet, Colorado County receives approximately 70.5 inches of rainfall annually with predominantly clay soil. Summer highs average 90ยฐF, providing good warmth for Leeks during the growing season. Clay soil retains moisture well for Leeks, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Leeks root diseases.

Colorado County, TX (Zone 8b) Year-round
281 days
Last Spring Frost February 26
281 growing days
First Fall Frost December 4

Colorado County Soil Profile

Soil Type

Clay

Soil pH

7.3-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (116 days to spare)
Start indoors: Jan 8 Transplant: Feb 12 🍅 Harvest: May 14 – Jul 30
Recommended (50%) ✓ Fits season (113 days to spare)
Start indoors: Jan 22 Transplant: Feb 26 🍅 Harvest: May 28 – Aug 13
Safe Start (90%) ✓ Fits season (105 days to spare)
Start indoors: Feb 13 Transplant: Mar 20 🍅 Harvest: Jun 19 – Sep 4

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 Colorado County

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

Soil pH

Your soil pH (7.3โ€“7.8) is more alkaline than Leeks prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Heavy clay soil (42% clay) in Colorado County compacts easily and drains slowly. Amend with compost and avoid working soil when wet.

Drainage

Drainage is adequate for Leeks.

Organic Matter

Organic matter is moderate (2.8%). 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.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
1.1″/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 โ€” 1.9" 0" โ„๏ธ Dormant
Feb 3.5" 2.3" 1.2" ๐Ÿ’ง Light watering
Mar 3.5" 4.5" 0" โœ… Rainfall sufficient
Apr 3.5" 8" 0" โœ… Rainfall sufficient
May 3.5" 10.9" 0" โœ… Rainfall sufficient
Jun 3.5" 10.3" 0" โœ… Rainfall sufficient
Jul 3.5" 9.3" 0" โœ… Rainfall sufficient
Aug 3.5" 8.7" 0" โœ… Rainfall sufficient
Sep 3.5" 5.5" 0" โœ… Rainfall sufficient
Oct 3.5" 4.8" 0" โœ… Rainfall sufficient
Nov 3.5" 2.3" 1.2" ๐Ÿ’ง Light watering
Dec 3.5" 1.9" 1.6" ๐Ÿ’ง Light watering

Water needs are for active growing months only (Febโ€“Dec in Colorado County). Supplement amounts are based on average rainfall โ€” 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" 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.

Leeks needs ~2,100 GDD — county provides 4,935 GDD Excellent fit

Leeks Planting Timeline โ€” Colorado County, TX

Leeks Planting Calendar

Activity When Date Range
Start Indoors January 22 Jan 22 โ€“ Feb 5
Transplant Outdoors February 26 Feb 26 โ€“ Mar 12
Direct Sow February 12 Feb 12 โ€“ Mar 5
Harvest May 28 May 28 โ€“ Aug 13
Fall Sowing September 25 Sep 25 โ€“ Oct 9

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.8"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

90โ€“150 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

281 days in Colorado County

Growing Tips for Leeks in Colorado County

Direct sow Leeks outdoors after February 26 in Colorado County when soil has warmed and frost danger has passed.

With Colorado County's clay soil (42% clay), work in 3-4 inches of compost before planting Leeks. Avoid tilling when soil is wet to prevent compaction.

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 →

Frequently Asked Questions

When should I plant Leeks in Colorado County, TX?

Colorado County is in Zone 8b with an average last frost of February 26. Plan your Leeks planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Colorado County, TX?

Colorado County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is February 26 and first fall frost is December 4.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Colorado County gardeners in Zone 8b 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 Colorado County, TX. Local conditions may vary. Last updated: April 2026.