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When to Plant Shallot in Blanco County, TX

Shallots are a gourmet allium prized for their complex, sweet, and mild flavor. Each bulb multiplies into a cluster, making them easy and rewarding to grow.

Blanco County, Texas is in USDA Zone 8a. The average last spring frost is March 8 and the first fall frost is November 21, giving you a growing season of approximately 258 days.

At an elevation of 4,826 feet, Blanco County receives approximately 61.5 inches of rainfall annually with predominantly clay soil. Summer highs average 90ยฐF, providing good warmth for Shallot during the growing season. Clay soil retains moisture well for Shallot, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Shallot root diseases.

Blanco County, TX (Zone 8a) Long season
258 days
Last Spring Frost March 8
258 growing days
First Fall Frost November 21

Blanco County Soil Profile

Soil Type

Clay

Soil pH

7.1-7.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (116 days to spare)
Start indoors: Jan 25 Transplant: Mar 1 🍅 Harvest: May 31 – Jul 19
Recommended (50%) ✓ Fits season (118 days to spare)
Start indoors: Feb 1 Transplant: Mar 8 🍅 Harvest: Jun 7 – Jul 26
Safe Start (90%) ✓ Fits season (107 days to spare)
Start indoors: Mar 3 Transplant: Apr 7 🍅 Harvest: Jul 7 – Aug 25

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 Blanco County

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

Soil pH

Your soil pH (7.1โ€“7.7) is more alkaline than Shallot prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Your clay soil in Blanco County is workable for Shallot. Add compost annually to improve structure.

Organic Matter

Organic matter is moderate (3.1%). Annual compost additions will help Shallot.

How to Plant Shallot

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

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

Plant Water Budget

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

Monthly Watering Guide for Shallot

Shallot needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Shallot Needs Rainfall You Supplement Action
Jan โ€” 1.6" 0" โ„๏ธ Dormant
Feb โ€” 1.8" 0" โ„๏ธ Dormant
Mar 4.3" 4.3" 0" โœ… Rainfall sufficient
Apr 4.3" 5.8" 0" โœ… Rainfall sufficient
May 4.3" 10.3" 0" โœ… Rainfall sufficient
Jun 4.3" 9.9" 0" โœ… Rainfall sufficient
Jul 4.3" 7.7" 0" โœ… Rainfall sufficient
Aug 4.3" 6.7" 0" โœ… Rainfall sufficient
Sep 4.3" 6.4" 0" โœ… Rainfall sufficient
Oct 4.3" 3.4" 0.9" ๐Ÿ’ง Light watering
Nov 4.3" 2" 2.3" ๐Ÿšฟ Regular watering
Dec โ€” 1.8" 0" โ„๏ธ Dormant

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

Shallot 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.

Shallot needs ~1,838 GDD — county provides 4,515 GDD Excellent fit

Shallot Planting Timeline โ€” Blanco County, TX

Shallot Planting Calendar

Activity When Date Range
Start Indoors February 1 Feb 1 โ€“ Feb 15
Transplant Outdoors March 8 Mar 8 โ€“ Mar 22
Direct Sow February 22 Feb 22 โ€“ Mar 15
Harvest June 7 Jun 7 โ€“ Jul 26
Fall Sowing September 12 Sep 12 โ€“ Sep 26

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

90โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

258 days in Blanco County

Growing Tips for Shallot in Blanco County

Direct sow Shallot outdoors after March 08 in Blanco County when soil has warmed and frost danger has passed.

With Blanco County's clay soil (36% clay), work in 3-4 inches of compost before planting Shallot. Avoid tilling when soil is wet to prevent compaction.

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

General growing tips

Plant sets in fall for spring harvest or early spring for summer harvest. Mulch heavily if overwintering. Harvest when tops brown and dry, then cure for storage.

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 Shallot in Blanco County, TX?

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

What planting zone is Blanco County, TX?

Blanco County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 8 and first fall frost is November 21.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Blanco 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 Blanco County, TX. Local conditions may vary. Last updated: April 2026.