Blog

When to Plant Bachelor's Button in Bexar County, TX

Bachelor's Button (Centaurea cyanus), also called cornflower, is a carefree cool-season annual best known for its vivid cobalt-blue flowers — one of the truest blues in the annual garden. It tolerates light frosts, self-seeds prolifically, and thrives in poor to average soils. A traditional cut flower and pollinator magnet, it has been cultivated in gardens for centuries.

Bexar County, Texas is in USDA Zone 9a. The average last spring frost is March 11 and the first fall frost is November 17, giving you a growing season of approximately 251 days.

At an elevation of 3,197 feet, Bexar County receives approximately 52.1 inches of rainfall annually with predominantly loam soil. Summer highs average 93°F, providing good warmth for Bachelor's Button during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Bachelor's Button root diseases.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Bexar County, TX (Zone 9a) Long season
251 days
Last Spring Frost March 11
251 growing days
First Fall Frost November 17

Bexar County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.8

Drainage

Well Drained

Monthly Watering Guide for Bachelor's Button

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

Month Bachelor's Button Needs Rainfall You Supplement Action
Jan 1.4" 0" ❄️ Dormant
Feb 1.7" 0" ❄️ Dormant
Mar 4.3" 3.6" 0.7" 💧 Light watering
Apr 4.3" 5.6" 0" ✅ Rainfall sufficient
May 4.3" 7.5" 0" ✅ Rainfall sufficient
Jun 4.3" 8.2" 0" ✅ Rainfall sufficient
Jul 4.3" 6.3" 0" ✅ Rainfall sufficient
Aug 4.3" 6.3" 0" ✅ Rainfall sufficient
Sep 4.3" 4.9" 0" ✅ Rainfall sufficient
Oct 4.3" 3.5" 0.8" 💧 Light watering
Nov 4.3" 1.9" 2.4" 🚿 Regular watering
Dec 1.3" 0" ❄️ Dormant

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

Bachelor's Button Planting Timeline — Bexar County, TX

Bachelor's Button Planting Calendar

Activity When Date Range
Transplant Outdoors February 11 Feb 11 – Feb 25
Direct Sow January 14 Jan 14 – Feb 4
Bloom April 8 Apr 8 – Jul 29
Fall Sowing September 8 Sep 8 – Sep 22

Plant 0.3" deep · 12" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January Direct Sow
February Transplant Outdoors Direct Sow
March
April Bloom
May Bloom
June Bloom
July Bloom
August
September Fall Sowing
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 9a

📆 Growing Season

251 days in Bexar County

Growing Tips for Bexar County

Direct-sow in early spring as soon as soil can be worked; seeds need a brief cold period for best germination (refrigerate for a few days before planting if spring arrives quickly). In zones 6+, fall-sow for the earliest spring bloom. Thin to 12 inches; do not over-fertilize — too much nitrogen produces foliage at the expense of flowers. Deadhead to prolong blooming or allow self-seeding for a naturalized colony.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Bachelor's Button in Bexar County, TX?

Bexar County is in Zone 9a with an average last frost of March 11. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.

What planting zone is Bexar County, TX?

Bexar County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 11 and first fall frost is November 17.

🌱

Your Bexar County Garden Planner — Free

A 22-page printable planner built for Bexar County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Bexar County, TX. Local conditions may vary. Last updated: June 2026.

Sources & credits

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