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When to Plant Garlic in Jackson County, OR

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.

Jackson County, Oregon is in USDA Zone 8a. The average last spring frost is May 7 and the first fall frost is October 10, giving you a growing season of approximately 156 days.

At an elevation of 422 feet, Jackson County receives approximately 46 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Garlic during the growing season.

Jackson County, OR (Zone 8a) Moderate season
156 days
Last Spring Frost May 7
156 growing days
First Fall Frost October 10

Jackson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (265 days to spare)
Transplant: Apr 26 🍅 Harvest: Jul 26 – Jan 10
Recommended (50%) ✓ Fits season (262 days to spare)
Transplant: May 7 🍅 Harvest: Aug 6 – Jan 21
Safe Start (90%) ✓ Fits season (266 days to spare)
Transplant: Jun 2 🍅 Harvest: Sep 1 – Feb 16

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 Jackson County

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

Soil pH

Your soil pH (5.3โ€“6.4) is more acidic than Garlic prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Garlic.

Organic Matter

Organic matter is excellent (5.0%) โ€” Garlic will thrive.

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
1.2″/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€” 6.1" 0" โ„๏ธ Dormant
Feb โ€” 5.8" 0" โ„๏ธ Dormant
Mar โ€” 5.1" 0" โ„๏ธ Dormant
Apr โ€” 3" 0" โ„๏ธ Dormant
May 2.2" 2.8" 0" โœ… Rainfall sufficient
Jun 2.2" 1.7" 0.5" ๐Ÿ’ง Light watering
Jul 2.2" 0.7" 1.5" ๐Ÿšฟ Regular watering
Aug 2.2" 1" 1.2" ๐Ÿšฟ Regular watering
Sep 2.2" 1.8" 0.4" ๐Ÿ’ง Light watering
Oct 2.2" 3.5" 0" โœ… Rainfall sufficient
Nov โ€” 6.4" 0" โ„๏ธ Dormant
Dec โ€” 8.2" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Jackson 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 ~2,640 GDD — county provides 2,496 GDD Tight fit

Garlic Planting Timeline โ€” Jackson County, OR

Garlic Planting Calendar

Activity When Date Range
Fall Sowing August 29 Aug 29 โ€“ Sep 12

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 Fall Sowing
September Fall Sowing
October โ€”
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: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

156 days in Jackson County

Growing Tips for Garlic in Jackson County

Direct sow Garlic outdoors after May 07 in Jackson County when soil has warmed and frost danger has passed.

Your 156.0-day growing season in Jackson 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 Jackson County, OR?

Jackson County is in Zone 8a with an average last frost of May 7. Plan your Garlic planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Jackson County, OR?

Jackson County, Oregon is in USDA Hardiness Zone 8a. The average last spring frost is May 7 and first fall frost is October 10.

๐ŸŒฑ

Plan Your Garden with Confidence

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