When to plant Alliums in Harrison County, MO
Harrison County gardeners should plant Alliums between mid-spring and late spring in spring. With Harrison County's Zone 5b climate (last frost April 19), Alliums needs 28–42 days to mature — plant by September 3 for a full harvest. A second sowing from September 3 to September 17 extends the harvest into fall.
When to Plant Alliums in Harrison County, MO
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.
Harrison County, Missouri is in USDA Zone 5b. The average last spring frost is April 19 and the first fall frost is October 15, giving you a growing season of approximately 179 days.
At an elevation of 1,349 feet, Harrison County receives approximately 37.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Alliums to ensure they mature before fall.
Harrison County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Alliums Planting Timeline — Harrison County, MO
Alliums Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Bloom | October 8 | Oct 8 – Oct 29 |
| Fall Sowing | September 3 | Sep 3 – Sep 17 |
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 | — |
| 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 5b
📆 Growing Season
179 days in Harrison County
Growing Tips for Harrison 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
Check more plant combinations with our Companion Planting Checker →
Alliums in Other Locations
Frequently Asked Questions
When should I plant Alliums in Harrison County, MO?
Harrison County is in Zone 5b with an average last frost of April 19. Plan your Alliums planting based on this frost date — see the calendar above for exact timing.
What planting zone is Harrison County, MO?
Harrison County, Missouri is in USDA Hardiness Zone 5b. The average last spring frost is April 19 and first fall frost is October 15.
When should I plant Alliums in Harrison County, MO?
In Harrison County, MO, plant Alliums after the last frost (around April 19) and before the first frost (around October 15). Best results when soil holds above 50°F.
What growing zone is Harrison County, MO for Alliums?
Harrison County sits in USDA Zone 5b. Alliums grows reliably in zones 3a through 9b, so it's a good fit here.
Can Alliums grow in Harrison County's climate?
Yes — Alliums grows well in Harrison County's temperate climate. Harrison County averages a 179-day frost-free season, with last frost around April 19 and first frost around October 15.
Your Harrison County Garden Planner — Free
A 22-page printable planner built for Harrison County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.