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When to plant Alliums in Frederick County, MD

Frederick County's climate puts the Alliums spring window between mid-spring and late spring. most warm-season crops establish quickly once soil holds above 60°F. A second sowing from September 18 to October 2 extends the harvest into fall.

When to Plant Alliums in Frederick County, MD

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.

Frederick County, Maryland is in USDA Zone 7a. The average last spring frost is April 16 and the first fall frost is October 23, giving you a growing season of approximately 190 days.

At an elevation of 756 feet, Frederick County receives approximately 49.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Alliums during the growing season.

Bulb Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Frederick County, MD (Zone 7a) Moderate season
190 days
Last Spring Frost April 16
190 growing days
First Fall Frost October 23

Frederick County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Alliums Planting Timeline — Frederick County, MD

Alliums Planting Calendar

Activity When Date Range
Bloom October 16 Oct 16 – Nov 6
Fall Sowing September 18 Sep 18 – Oct 2

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

190 days in Frederick County

Growing Tips for Frederick 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 Frederick County, MD?

Frederick County is in Zone 7a with an average last frost of April 16. Plan your Alliums planting based on this frost date — see the calendar above for exact timing.

What planting zone is Frederick County, MD?

Frederick County, Maryland is in USDA Hardiness Zone 7a. The average last spring frost is April 16 and first fall frost is October 23.

When should I plant Alliums in Frederick County, MD?

In Frederick County, MD, plant Alliums after the last frost (around April 16) and before the first frost (around October 23). Best results when soil holds above 50°F.

What growing zone is Frederick County, MD for Alliums?

Frederick 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 Frederick County's climate?

Yes — Alliums grows well in Frederick County's temperate climate. Frederick County averages a 190-day frost-free season, with last frost around April 16 and first frost around October 23.

🌱

Your Frederick County Garden Planner — Free

A 22-page printable planner built for Frederick 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 Frederick County, MD. Local conditions may vary. Last updated: July 2026.

Sources & credits

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