Blog

When to plant Bachelor's Button in St. Johns County County,

St. Johns County County sits in USDA Zone 9b. Plant Bachelor's Button between December 8 (after last frost on February 9) and December 29. A second sowing from September 23 to October 7 extends the harvest into fall.

When to Plant Bachelor's Button in St. Johns County, FL

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.

St. Johns County, Florida is in USDA Zone 9b. The average last spring frost is February 9 and the first fall frost is December 2, giving you a growing season of approximately 296 days.

At an elevation of 57 feet, St. Johns County receives approximately 51.1 inches of rainfall annually with predominantly sand soil. Summer highs average 99°F, so Bachelor's Button may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Bachelor's Button will need more frequent watering and organic matter to retain nutrients. 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
St. Johns County, FL (Zone 9b) Year-round
296 days
Last Spring Frost February 9
296 growing days
First Fall Frost December 2
Share this guide:

St. Johns County Soil Profile

Soil Type

Sand

Soil pH

4.9-6.1

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 2.4" 0" ❄️ Dormant
Feb 4.3" 2.4" 1.9" 💧 Light watering
Mar 4.3" 2.8" 1.5" 💧 Light watering
Apr 4.3" 2.8" 1.5" 💧 Light watering
May 4.3" 3.5" 0.8" 💧 Light watering
Jun 4.3" 7" 0" ✅ Rainfall sufficient
Jul 4.3" 7.1" 0" ✅ Rainfall sufficient
Aug 4.3" 7.6" 0" ✅ Rainfall sufficient
Sep 4.3" 6.9" 0" ✅ Rainfall sufficient
Oct 4.3" 4.3" 0" ✅ Rainfall sufficient
Nov 4.3" 2.1" 2.2" 🚿 Regular watering
Dec 4.3" 2.3" 2" 💧 Light watering

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

Bachelor's Button Planting Timeline — St. Johns County, FL

Bachelor's Button Planting Calendar

Activity When Date Range
Transplant Outdoors January 5 Jan 5 – Jan 19
Direct Sow December 8 Dec 8 – Dec 29
Bloom March 2 Mar 2 – Jun 22
Fall Sowing September 23 Sep 23 – Oct 7

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

Month-by-Month Timeline

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

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 9b

📆 Growing Season

296 days in St. Johns County

Growing Tips for St. Johns 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 St. Johns County, FL?

St. Johns County is in Zone 9b with an average last frost of February 9. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.

What planting zone is St. Johns County, FL?

St. Johns County, Florida is in USDA Hardiness Zone 9b. The average last spring frost is February 9 and first fall frost is December 2.

When should I plant Bachelor's Button in St. Johns County County, ?

In St. Johns County County, , plant Bachelor's Button after the last frost (around February 9) and before the first frost (around December 2). Best results when soil holds above 50°F.

What growing zone is St. Johns County County, for Bachelor's Button?

St. Johns County County sits in USDA Zone 9b. Bachelor's Button grows reliably in zones 2a through 11b, so it's a good fit here.

Can Bachelor's Button grow in St. Johns County County's climate?

Yes — Bachelor's Button grows well in St. Johns County County's temperate climate. St. Johns County County averages a 297-day frost-free season, with last frost around February 9 and first frost around December 2.

🌱

Your St. Johns County Garden Planner — Free

A 22-page printable planner built for St. Johns County (Zone 9b). 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 St. Johns County, FL. 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.