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When to Plant Yarrow in Smith County, TX

Smith County, Texas Zone 8b May

May to-do list for Smith County, Texas

May is a pivotal month for Smith County, Texas gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost March 9
Avg. first frost November 16
Soil temp (4") 72°F
Watering Low
Pest pressure High
Daylight 13.7 hrs
June will be here before you know it — start on
  • First harvests: yarrow

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Yarrow is a drought-tolerant perennial herb with feathery foliage and flat-topped flower clusters in white, yellow, pink, or red. It attracts beneficial insects and is used in herbal medicine.

Smith County, Texas is in USDA Zone 8b. The average last spring frost is March 9 and the first fall frost is November 16, giving you a growing season of approximately 252 days.

At an elevation of 179 feet, Smith County receives approximately 59.5 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 96°F, so Yarrow may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Yarrow will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Yarrow root diseases.

Smith County, TX (Zone 8b) Long season
252 days
Last Spring Frost March 9
252 growing days
First Fall Frost November 16

Smith County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.6-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (82 days to spare)
Transplant: Mar 7 🍅 Harvest: Jun 6 – Aug 22
Recommended (50%) ✓ Fits season (77 days to spare)
Transplant: Mar 16 🍅 Harvest: Jun 15 – Aug 31
Safe Start (90%) ✓ Fits season (72 days to spare)
Transplant: Apr 5 🍅 Harvest: Jul 5 – Sep 20

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 Smith County

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

Soil pH

Your soil pH (5.6–6.5) is within Yarrow's preferred range (5.5–7.0).

Soil Texture

Sandy soil in Smith County warms quickly in spring but drains fast. Yarrow will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

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

How to Plant Yarrow

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Plant Water Budget

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

Monthly Watering Guide for Yarrow

Yarrow 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 Yarrow Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 1.8" 0" ❄️ Dormant
Mar 2.2" 3.7" 0" ✅ Rainfall sufficient
Apr 2.2" 6.5" 0" ✅ Rainfall sufficient
May 2.2" 8.1" 0" ✅ Rainfall sufficient
Jun 2.2" 8.7" 0" ✅ Rainfall sufficient
Jul 2.2" 8.1" 0" ✅ Rainfall sufficient
Aug 2.2" 6.8" 0" ✅ Rainfall sufficient
Sep 2.2" 6.2" 0" ✅ Rainfall sufficient
Oct 2.2" 4.2" 0" ✅ Rainfall sufficient
Nov 2.2" 2.2" 0" ✅ Rainfall sufficient
Dec 1.6" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Smith County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Yarrow 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.

Yarrow needs ~2,310 GDD — county provides 5,544 GDD Excellent fit

Yarrow Planting Timeline — Smith County, TX

Yarrow Planting Calendar

Activity When Date Range
Transplant Outdoors March 16 Mar 16 – Mar 30
Harvest June 15 Jun 15 – Aug 31

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March Transplant Outdoors
April
May
June Harvest
July Harvest
August Harvest
September
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

90–120 days

🧪 Soil pH

Needs 5.5–7 · Your soil: ideal

🗺️ USDA Zone

Zone 8b

📆 Growing Season

252 days in Smith County

Growing Tips for Yarrow in Smith County

Direct sow Yarrow outdoors after March 09 in Smith County when soil has warmed and frost danger has passed.

Sandy soil in Smith County dries quickly — mulch Yarrow with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 96°F in Smith County, provide afternoon shade for Yarrow and water deeply in the morning.

Common pests for Yarrow in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow or start from divisions. Yarrow thrives in poor soil and is very drought-tolerant. Deadhead to encourage reblooming. Divide clumps every 3 years.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Yarrow in Smith County, TX?

Smith County is in Zone 8b with an average last frost of March 9. Plan your Yarrow planting based on this frost date — see the calendar above for exact timing.

What planting zone is Smith County, TX?

Smith County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 9 and first fall frost is November 16.

🌱

Your Smith County Garden Planner — Free

A 24-page printable planner built for Smith County (Zone 8b). 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 Smith County, TX. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.