When to plant Alliums in Bent County, CO
Plant Alliums in Bent County from mid-spring to late spring in spring. Bent County sits in USDA Zone 6a, with last frost around April 29 and first frost on October 9. A second sowing from August 28 to September 11 extends the harvest into fall.
When to Plant Alliums in Bent County, CO
Your June gardening checklist
If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.
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.
Bent County, Colorado is in USDA Zone 6a. The average last spring frost is April 29 and the first fall frost is October 9, giving you a growing season of approximately 163 days.
At an elevation of 4,516 feet, Bent County receives approximately 12.4 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Alliums during the growing season. With low rainfall, drip irrigation is essential for growing Alliums successfully. Mulch heavily to conserve soil moisture.
Bent County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.8
Drainage
Well Drained
Alliums Planting Risk Windows
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 Bent County
How your county's soil matches Alliums's growing requirements.
Soil pH
Your soil pH (6.8–7.8) overlaps with Alliums's range (5.5–7.5), though not a perfect match.
Soil Texture
The loam soil in Bent County is excellent for Alliums — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.5%). Annual compost additions will help Alliums.
How to Plant Alliums
Fall planting: Sow 6 weeks before your first frost date for a fall harvest.
Succession Planting Alliums
Sow every 3.1 weeks. Last sowing by Aug 28 to harvest before frost.
For a dedicated fall crop, sow by Aug 28.
Alliums Water Budget
Water stress score is 8/10 — 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 | — | 0.9" | 0" | ❄️ Dormant |
| Feb | — | 0.6" | 0" | ❄️ Dormant |
| Mar | — | 1" | 0" | ❄️ Dormant |
| Apr | 2.2" | 1.4" | 0.8" | 💧 Light watering |
| May | 2.2" | 1.6" | 0.6" | 💧 Light watering |
| Jun | 2.2" | 0.9" | 1.3" | 🚿 Regular watering |
| Jul | 2.2" | 1" | 1.2" | 🚿 Regular watering |
| Aug | 2.2" | 1.4" | 0.8" | 💧 Light watering |
| Sep | 2.2" | 1" | 1.2" | 🚿 Regular watering |
| Oct | 2.2" | 1.1" | 1.1" | 🚿 Regular watering |
| Nov | — | 0.8" | 0" | ❄️ Dormant |
| Dec | — | 0.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Bent 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 Planting Timeline — Bent County, CO
Alliums Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Bloom | September 25 | Sep 25 – Oct 23 |
| Fall Sowing | August 28 | Aug 28 – Sep 11 |
Plant 5" deep · 7" apart · Rows 8" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | — |
| June | — |
| July | — |
| August | Fall Sowing |
| September | Fall Sowing Bloom |
| October | Bloom |
| November | — |
| 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: acceptable
🗺️ USDA Zone
Zone 6a
📆 Growing Season
163 days in Bent County
Growing Tips for Alliums in Bent County
Direct sow Alliums outdoors after April 29 in Bent County when soil has warmed and frost danger has passed.
Your generous 163.0-day season in Bent 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.
Bent County receives only 12" 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
Check more plant combinations with our Companion Planting Checker →
Alliums in Other Locations
Frequently Asked Questions
When should I plant Alliums in Bent County, CO?
Bent County is in Zone 6a with an average last frost of April 29. Plan your Alliums planting based on this frost date — see the calendar above for exact timing.
What planting zone is Bent County, CO?
Bent County, Colorado is in USDA Hardiness Zone 6a. The average last spring frost is April 29 and first fall frost is October 9.
When should I plant Alliums in Bent County, CO?
In Bent County, CO, plant Alliums after the last frost (around April 29) and before the first frost (around October 9). Best results when soil holds above 50°F.
What growing zone is Bent County, CO for Alliums?
Bent County sits in USDA Zone 6a. Alliums grows reliably in zones 3a through 9b, so it's a good fit here.
Can Alliums grow in Bent County's climate?
Yes — Alliums grows well in Bent County's temperate climate. Bent County averages a 163-day frost-free season, with last frost around April 29 and first frost around October 9.
Your Bent County Garden Planner — Free
A 22-page printable planner built for Bent County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.