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When to Plant Garlic in Knox County, TX

Garlic is a pungent allium planted in fall and harvested the following summer. Hardneck varieties produce edible flower stalks (scapes) and are more cold-hardy.

Knox County, Texas is in USDA Zone 7b. The average last spring frost is March 24 and the first fall frost is November 12, giving you a growing season of approximately 233 days.

At an elevation of 1,847 feet, Knox County receives approximately 51.2 inches of rainfall annually with predominantly loam soil. Summer highs average 93ยฐF, providing good warmth for Garlic during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Garlic root diseases.

Knox County, TX (Zone 7b) Long season
233 days
Last Spring Frost March 24
233 growing days
First Fall Frost November 12

Knox County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (6 days to spare)
Transplant: Mar 17 🍅 Harvest: Jun 16 – Oct 27
Recommended (50%) ✓ Fits season (9 days to spare)
Transplant: Mar 24 🍅 Harvest: Jun 23 – Nov 3
Safe Start (90%) ✓ Fits season (2 days to spare)
Transplant: Apr 13 🍅 Harvest: Jul 13 – Nov 23

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 Knox County

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

Soil pH

Your soil pH (6.4โ€“7.2) is within Garlic's preferred range (6.0โ€“7.5).

Soil Texture

The loam soil in Knox County is excellent for Garlic โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is low (1.9%). Add 2-3 inches of compost before planting Garlic.

How to Plant Garlic

1"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 6 weeks before your first frost date for a fall harvest.

Plant Water Budget

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

Monthly Watering Guide for Garlic

Garlic needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Garlic Needs Rainfall You Supplement Action
Jan โ€” 1.3" 0" โ„๏ธ Dormant
Feb โ€” 2.1" 0" โ„๏ธ Dormant
Mar 2.2" 3.2" 0" โœ… Rainfall sufficient
Apr 2.2" 6.4" 0" โœ… Rainfall sufficient
May 2.2" 6.7" 0" โœ… Rainfall sufficient
Jun 2.2" 7.3" 0" โœ… Rainfall sufficient
Jul 2.2" 6.5" 0" โœ… Rainfall sufficient
Aug 2.2" 5.9" 0" โœ… Rainfall sufficient
Sep 2.2" 5.4" 0" โœ… Rainfall sufficient
Oct 2.2" 3.3" 0" โœ… Rainfall sufficient
Nov 2.2" 1.8" 0.4" ๐Ÿ’ง Light watering
Dec โ€” 1.3" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Knox County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Garlic 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.

Garlic needs ~3,259 GDD — county provides 4,601 GDD Excellent fit

Garlic Planting Timeline โ€” Knox County, TX

Garlic Planting Calendar

Activity When Date Range
Fall Sowing October 1 Oct 1 โ€“ Oct 15

Plant 1" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May โ€”
June โ€”
July โ€”
August โ€”
September โ€”
October Fall Sowing
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

90โ€“240 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

233 days in Knox County

Growing Tips for Garlic in Knox County

Direct sow Garlic outdoors after March 24 in Knox County when soil has warmed and frost danger has passed.

Your 233.0-day growing season in Knox County is tight for Garlic (90.0-240.0 days to maturity). Start indoors and choose early-maturing varieties.

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

General growing tips

Plant individual cloves pointed end up in fall, 6 weeks before ground freezes. Mulch heavily with straw. Harvest when lower leaves begin to brown but 5-6 green leaves remain.

Companion Planting

Good Companions

Avoid Planting Near

  • Peas
  • Green Beans
  • Asparagus

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Garlic in Knox County, TX?

Knox County is in Zone 7b with an average last frost of March 24. Plan your Garlic planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Knox County, TX?

Knox County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 24 and first fall frost is November 12.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Knox County gardeners in Zone 7b 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 Knox County, TX. Local conditions may vary. Last updated: April 2026.