When to Plant Irises in Kimball County, NE
Bearded Iris (Iris germanica) are among the most regal flowers of the late-spring garden, producing elegantly ruffled blooms in virtually every color of the rainbow — often in spectacular bicolor combinations. Named for the fuzzy "beard" on the lower falls (petals), bearded irises grow from thick horizontal rhizomes that spread to form dense clumps over time. Individual blooms last only a few days, but a well-established clump produces successive flowers over 3–4 weeks. Many are intensely fragrant. Native iris species including blue flag iris (I. versicolor) and Virginia iris (I. virginica) are excellent choices for wet or native garden settings.
Kimball County, Nebraska is in USDA Zone 5a. The average last spring frost is May 12 and the first fall frost is October 2, giving you a growing season of approximately 143 days.
At an elevation of 920 feet, Kimball County receives approximately 20.2 inches of rainfall annually with predominantly loam soil. Summer highs average 81°F, so choose short-season varieties of Irises to ensure they mature before fall.
Kimball County Soil Profile
Soil Type
Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Irises Planting Timeline — Kimball County, NE
Irises Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 26 | May 26 – Jun 9 |
| Bloom | July 21 | Jul 21 – Aug 25 |
Plant 0.5" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | Transplant Outdoors |
| July | Bloom |
| August | Bloom |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
60–100 days
🧪 Soil pH
Needs 6.8–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5a
📆 Growing Season
143 days in Kimball County
Growing Tips for Kimball County
Plant rhizomes in late summer to early fall (July–September) after bloom season, setting them horizontally with the top of the rhizome at or just slightly below soil surface — never deeply buried. Full sun is essential for best bloom; at least 6 hours. Well-drained soil is critical; wet rhizomes rot in winter. After bloom, remove flower stalks but leave foliage until it browns in fall. Divide every 3–5 years in late summer when clumps become congested (crowded rhizomes stop blooming). Iris borer is the primary pest — remove and destroy affected fans. Year 2+ after division delivers the most bloom; freshly divided rhizomes may have limited or no bloom in their first season.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Irises in Other Locations
Frequently Asked Questions
When should I plant Irises in Kimball County, NE?
Kimball County is in Zone 5a with an average last frost of May 12. Plan your Irises planting based on this frost date — see the calendar above for exact timing.
What planting zone is Kimball County, NE?
Kimball County, Nebraska is in USDA Hardiness Zone 5a. The average last spring frost is May 12 and first fall frost is October 2.
Your Kimball County Garden Planner — Free
A 22-page printable planner built for Kimball County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.