Blog

When to Plant Bachelor's Button in Smyth County, VA

Smyth County, Virginia Zone 7a June

June in the garden — Smyth County, Virginia

June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Smyth County, Virginia.

Avg. last frost May 2
Avg. first frost October 12
Soil temp (4") 73°F
Watering Low
Pest pressure High
Daylight 14.5 hrs

Instant PDF download. No spam, unsubscribe any time.

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.

Smyth County, Virginia is in USDA Zone 7a. The average last spring frost is May 2 and the first fall frost is October 12, giving you a growing season of approximately 163 days.

At an elevation of 375 feet, Smyth County receives approximately 51.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°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
Smyth County, VA (Zone 7a) Moderate season
163 days
Last Spring Frost May 2
163 growing days
First Fall Frost October 12

Smyth County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.8

Drainage

Well Drained

Bachelor's Button Planting Risk Windows

Early Start (70% safe) ✓ Fits season (8 days to spare)
Start indoors: Mar 13 Transplant: Apr 24 🌸 Bloom: Jun 26 – Sep 25
Recommended (50%) ✓ Fits season (9 days to spare)
Start indoors: Mar 21 Transplant: May 2 🌸 Bloom: Jul 4 – Oct 3
Safe Start (90%) ✓ Fits season (6 days to spare)
Start indoors: Apr 7 Transplant: May 19 🌸 Bloom: Jul 21 – Oct 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 Smyth County

How your county's soil matches Bachelor's Button's growing requirements.

Soil pH

Your soil pH (5.3–6.8) overlaps with Bachelor's Button's range (6.0–7.5), though not a perfect match.

Soil Texture

The silt loam soil in Smyth County is excellent for Bachelor's Button — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.5%). Annual compost additions will help Bachelor's Button.

How to Plant Bachelor's Button

0.3"
Planting Depth
12"
Between Plants
12"
Between Rows

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Bachelor's Button

3
successive plantings in your 163-day season

Sow every 6.9 weeks. Last sowing by Jul 14 to harvest before frost.

For a dedicated fall crop, sow by Aug 17.

Bachelor's Button Water Budget

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

Monthly Watering Guide for Bachelor's Button

Bachelor's Button 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 Bachelor's Button Needs Rainfall You Supplement Action
Jan 3.9" 0" ❄️ Dormant
Feb 3.9" 0" ❄️ Dormant
Mar 4.6" 0" ❄️ Dormant
Apr 4.3" 0" ❄️ Dormant
May 2.2" 4.1" 0" ✅ Rainfall sufficient
Jun 2.2" 4.2" 0" ✅ Rainfall sufficient
Jul 2.2" 5.4" 0" ✅ Rainfall sufficient
Aug 2.2" 5.7" 0" ✅ Rainfall sufficient
Sep 2.2" 3.5" 0" ✅ Rainfall sufficient
Oct 2.2" 3.3" 0" ✅ Rainfall sufficient
Nov 3.7" 0" ❄️ Dormant
Dec 4.5" 0" ❄️ Dormant

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

Bachelor's Button 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.

Bachelor's Button needs ~1,088 GDD — county provides 2,363 GDD Excellent fit

Bachelor's Button Planting Timeline — Smyth County, VA

Bachelor's Button Planting Calendar

Activity When Date Range
Start Indoors March 21 Mar 21 – Apr 4
Transplant Outdoors May 2 May 2 – May 16
Direct Sow March 28 Mar 28 – Apr 18
Bloom July 4 Jul 4 – Oct 3
Fall Sowing August 17 Aug 17 – Aug 31

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

163 days in Smyth County

Growing Tips for Bachelor's Button in Smyth County

Direct sow Bachelor's Button outdoors after May 02 in Smyth County when soil has warmed and frost danger has passed.

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

General growing tips

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 Smyth County, VA?

Smyth County is in Zone 7a with an average last frost of May 2. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.

What planting zone is Smyth County, VA?

Smyth County, Virginia is in USDA Hardiness Zone 7a. The average last spring frost is May 2 and first fall frost is October 12.

🌱

Your Smyth County Garden Planner — Free

A 22-page printable planner built for Smyth County (Zone 7a). 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 Smyth County, VA. 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.