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When to plant Alliums in Union County, KY

For Alliums in Union County, the safe spring window opens around mid-spring and closes around late spring. Last expected frost is April 6, first fall frost October 31, giving a 208-day growing season. A second sowing from September 26 to October 10 extends the harvest into fall.

When to Plant Alliums in Union County, KY

Ornamental alliums (Allium spp.) bridge the gap between spring and summer with their striking globe-shaped flower heads in shades of purple, violet, white, and pink. Blooming after tulips have faded, they extend the spring display well into early summer. 'Gladiator', 'Globemaster', and 'Purple Sensation' produce softball-sized heads on 18–36 inch stems, while smaller species create charming accents at border fronts. Deer and rodents shun them completely due to the characteristic onion scent. Dried seed heads provide architectural interest into fall.

Union County, Kentucky is in USDA Zone 7a. The average last spring frost is April 6 and the first fall frost is October 31, giving you a growing season of approximately 208 days.

At an elevation of 1,482 feet, Union County receives approximately 48.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Alliums during the growing season.

Bulb Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Union County, KY (Zone 7a) Long season
208 days
Last Spring Frost April 6
208 growing days
First Fall Frost October 31

Union County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Alliums Planting Timeline — Union County, KY

Alliums Planting Calendar

Activity When Date Range
Bloom October 24 Oct 24 – Nov 14
Fall Sowing September 26 Sep 26 – Oct 10

Plant 5" deep · 7" apart · Rows 8" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

28–42 days

🧪 Soil pH

Needs 5.5–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 7a

📆 Growing Season

208 days in Union County

Growing Tips for Union County

Plant bulbs in fall, 3–4 times as deep as the bulb diameter (typically 4–6 inches for large types, 3 inches for small species). Space 6–8 inches apart for standard cultivars. Foliage often looks untidy as it dies back before bloom — plant around perennials that will conceal the yellowing leaves. Excellent drainage is essential; alliums rot in wet soils. Leave bulbs in place for naturalization; divide every 3–4 years when clusters become congested. Deadhead spent globes or leave for ornamental seedheads and self-sowing.

Companion Planting

Good Companions

Avoid Planting Near

  • Beans
  • Peas

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Alliums in Union County, KY?

Union County is in Zone 7a with an average last frost of April 6. Plan your Alliums planting based on this frost date — see the calendar above for exact timing.

What planting zone is Union County, KY?

Union County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 6 and first fall frost is October 31.

When should I plant Alliums in Union County, KY?

In Union County, KY, plant Alliums after the last frost (around April 6) and before the first frost (around October 31). Best results when soil holds above 50°F.

What growing zone is Union County, KY for Alliums?

Union County sits in USDA Zone 7a. Alliums grows reliably in zones 3a through 9b, so it's a good fit here.

Can Alliums grow in Union County's climate?

Yes — Alliums grows well in Union County's temperate climate. Union County averages a 208-day frost-free season, with last frost around April 6 and first frost around October 31.

🌱

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A 22-page printable planner built for Union 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.

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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 Union County, KY. Local conditions may vary. Last updated: June 2026.

Sources & credits

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