When to plant Alliums in Unity, IL
Unity gardeners should plant Alliums between mid-spring and late spring in spring. With Unity's Zone 7a climate (last frost April 10), Alliums needs 28–42 days to mature — plant by September 9 for a full harvest. A second sowing from September 16 to September 30 extends the harvest into fall.
When to Plant Alliums in Unity, IL
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.
Unity, Illinois is in USDA Zone 7a. The average last spring frost is April 10 and the first fall frost is October 21, giving you a growing season of approximately 194 days.
At an elevation of 1,260 feet, Alexander County receives approximately 38.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Alliums during the growing season.
Unity Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-7
Drainage
Well Drained
Monthly Watering Guide for Alliums
Alliums needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Alliums Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 3" | 0" | ❄️ Dormant |
| Apr | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Jun | 4.3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Aug | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 3" | 1.3" | 💧 Light watering |
| Oct | 4.3" | 3" | 1.3" | 💧 Light watering |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Alexander County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Alliums Planting Timeline — Unity, IL
Alliums Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Bloom | October 14 | Oct 14 – Nov 4 |
| Fall Sowing | September 16 | Sep 16 – Sep 30 |
Plant 5" deep · 7" apart · Rows 8" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | — |
| June | — |
| July | — |
| August | — |
| September | Fall Sowing |
| October | 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
194 days in Alexander County
Growing Tips for Unity
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
When should I plant Alliums in Unity, IL?
In Unity, IL, plant Alliums after the last frost (around April 10) and before the first frost (around October 21). Best results when soil holds above 50°F.
What growing zone is Unity, IL for Alliums?
Unity sits in USDA Zone 7a. Alliums grows reliably in zones 3a through 9b, so it's a good fit here.
Can Alliums grow in Unity's climate?
Yes — Alliums grows well in Unity's temperate climate. Unity averages a 194-day frost-free season, with last frost around April 10 and first frost around October 21.
Your Alexander County Garden Planner — Free
A 22-page printable planner built for Alexander 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.