When to plant Alliums in Harper County, KS
Alliums planted in Harper County between mid-spring and late spring matures in 28–42 days — well before the October 27 first frost. A second sowing from September 22 to October 6 extends the harvest into fall.
When to Plant Alliums in Harper County, KS
This month in Harper County, Kansas
Your Harper County, Kansas garden is entering a new phase. Here's what's on the schedule for July and why each task matters now.
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.
Harper County, Kansas is in USDA Zone 7a. The average last spring frost is April 9 and the first fall frost is October 27, giving you a growing season of approximately 201 days.
At an elevation of 745 feet, Harper County receives approximately 27.7 inches of rainfall annually with predominantly loam soil. Summer highs average 88°F, providing good warmth for Alliums during the growing season.
Harper County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.8
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 Harper County
How your county's soil matches Alliums's growing requirements.
Soil pH
Your soil pH (6.2–7.8) overlaps with Alliums's range (5.5–7.5), though not a perfect match.
Soil Texture
The loam soil in Harper County is excellent for Alliums — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Alliums.
Organic Matter
Organic matter is excellent (4.1%) — Alliums will thrive.
How to Plant Alliums
Fall planting: Sow 5 weeks before your first frost date for a fall harvest.
Succession Planting Alliums
Sow every 3.1 weeks. Last sowing by Sep 15 to harvest before frost.
For a dedicated fall crop, sow by Sep 22.
Alliums Water Budget
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 | — | 0.7" | 0" | ❄️ Dormant |
| Feb | — | 1.1" | 0" | ❄️ Dormant |
| Mar | — | 1.6" | 0" | ❄️ Dormant |
| Apr | 2.2" | 2.6" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2.7" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 1.9" | 0.3" | 💧 Light watering |
| Nov | — | 1" | 0" | ❄️ Dormant |
| Dec | — | 0.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Harper 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 — Harper County, KS
Alliums Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Bloom | October 20 | Oct 20 – Nov 10 |
| Fall Sowing | September 22 | Sep 22 – Oct 6 |
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 | 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: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
201 days in Harper County
Growing Tips for Alliums in Harper County
Direct sow Alliums outdoors after April 09 in Harper County when soil has warmed and frost danger has passed.
Your generous 201.0-day season in Harper 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.
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 Harper County, KS?
Harper County is in Zone 7a with an average last frost of April 9. Plan your Alliums planting based on this frost date — see the calendar above for exact timing.
What planting zone is Harper County, KS?
Harper County, Kansas is in USDA Hardiness Zone 7a. The average last spring frost is April 9 and first fall frost is October 27.
When should I plant Alliums in Harper County, KS?
In Harper County, KS, plant Alliums after the last frost (around April 9) and before the first frost (around October 27). Best results when soil holds above 50°F.
What growing zone is Harper County, KS for Alliums?
Harper 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 Harper County's climate?
Yes — Alliums grows well in Harper County's temperate climate. Harper County averages a 201-day frost-free season, with last frost around April 9 and first frost around October 27.
Your Harper County Garden Planner — Free
A 22-page printable planner built for Harper 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.