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When to Plant Alliums in Noble County, OK

Noble County, Oklahoma Zone 7a June

June to-do list for Noble County, Oklahoma

June is a pivotal month for Noble County, Oklahoma gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost April 7
Avg. first frost October 28
Soil temp (4") 78°F
Watering Low
Pest pressure High
Daylight 14.5 hrs

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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.

Noble County, Oklahoma is in USDA Zone 7a. The average last spring frost is April 7 and the first fall frost is October 28, giving you a growing season of approximately 204 days.

At an elevation of 547 feet, Noble County receives approximately 24.2 inches of rainfall annually with predominantly loam soil. Summer highs average 92°F, providing good warmth for Alliums during the growing season.

Bulb Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Noble County, OK (Zone 7a) Long season
204 days
Last Spring Frost April 7
204 growing days
First Fall Frost October 28

Noble County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.2

Drainage

Well Drained

Alliums Planting Risk Windows

Early Start (70% safe) ✓ Fits season (157 days to spare)
Transplant: Mar 31 🌸 Bloom: Apr 28 – May 19
Recommended (50%) ✓ Fits season (155 days to spare)
Transplant: Apr 7 🌸 Bloom: May 5 – May 26
Safe Start (90%) ✓ Fits season (161 days to spare)
Transplant: Apr 21 🌸 Bloom: May 19 – Jun 9

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 Noble County

How your county's soil matches Alliums's growing requirements.

Soil pH

Your soil pH (6.4–7.2) is within Alliums's preferred range (5.5–7.5).

Soil Texture

The loam soil in Noble County is excellent for Alliums — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Alliums.

Organic Matter

Organic matter is moderate (3.9%). Annual compost additions will help Alliums.

How to Plant Alliums

5"
Planting Depth
7"
Between Plants
8"
Between Rows

Fall planting: Sow 5 weeks before your first frost date for a fall harvest.

Succession Planting Alliums

9
successive plantings in your 204-day season

Sow every 3.1 weeks. Last sowing by Sep 16 to harvest before frost.

For a dedicated fall crop, sow by Sep 23.

Alliums Water Budget

Plant needs
0.5″/week
Rainfall provides
0.5″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 331 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Alliums

Alliums 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 Alliums Needs Rainfall You Supplement Action
Jan 0.6" 0" ❄️ Dormant
Feb 0.9" 0" ❄️ Dormant
Mar 1.6" 0" ❄️ Dormant
Apr 2.2" 2.3" 0" ✅ Rainfall sufficient
May 2.2" 3.8" 0" ✅ Rainfall sufficient
Jun 2.2" 3.9" 0" ✅ Rainfall sufficient
Jul 2.2" 2.8" 0" ✅ Rainfall sufficient
Aug 2.2" 3" 0" ✅ Rainfall sufficient
Sep 2.2" 2.2" 0" ✅ Rainfall sufficient
Oct 2.2" 1.7" 0.5" 💧 Light watering
Nov 0.8" 0" ❄️ Dormant
Dec 0.7" 0" ❄️ Dormant

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

Alliums 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.

Alliums needs ~665 GDD — county provides 3,876 GDD Excellent fit

Alliums Planting Timeline — Noble County, OK

Alliums Planting Calendar

Activity When Date Range
Bloom October 21 Oct 21 – Nov 11
Fall Sowing September 23 Sep 23 – Oct 7

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

0.5"/week · Only during dry spells

📅 Days to Maturity

28–42 days

🧪 Soil pH

Needs 5.5–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 7a

📆 Growing Season

204 days in Noble County

Growing Tips for Alliums in Noble County

Direct sow Alliums outdoors after April 07 in Noble County when soil has warmed and frost danger has passed.

Your generous 204.0-day season in Noble County allows multiple plantings of Alliums. Sow every 14.0 days for continuous harvest.

Common pests for Alliums in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.

Noble County receives only 24" of rain annually. Alliums needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

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 Noble County, OK?

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

What planting zone is Noble County, OK?

Noble County, Oklahoma is in USDA Hardiness Zone 7a. The average last spring frost is April 7 and first fall frost is October 28.

🌱

Your Noble County Garden Planner — Free

A 22-page printable planner built for Noble 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 Noble County, OK. 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.