When to plant Daffodils in Dubuque County, IA
For Daffodils in Dubuque County, the safe spring window opens around mid-spring and closes around late spring. Last expected frost is April 29, first fall frost October 9, giving a 163-day growing season. A second sowing from August 28 to September 11 extends the harvest into fall.
When to Plant Daffodils in Dubuque County, IA
Daffodils (Narcissus spp.) are among the most dependable and longest-lived of all spring bulbs. Their cheerful yellow and white blooms emerge in early spring, often while frost is still possible, bringing color weeks before most other flowers. Unlike tulips, established clumps naturalize readily — spreading and returning reliably year after year without replanting. Deer and rodents avoid them due to toxic alkaloids in the bulb and sap, making them a low-maintenance choice for naturalized areas, woodland edges, and mixed borders.
Dubuque County, Iowa is in USDA Zone 5a. 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 1,243 feet, Dubuque County receives approximately 36.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Daffodils to ensure they mature before fall.
Dubuque County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Daffodils Planting Timeline — Dubuque County, IA
Daffodils Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Bloom | July 17 | Jul 17 – Aug 7 |
| Fall Sowing | August 28 | Aug 28 – Sep 11 |
Plant 7" deep · 7" apart · Rows 8" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | — |
| June | — |
| July | Bloom |
| August | Fall Sowing Bloom |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
20–40 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5a
📆 Growing Season
163 days in Dubuque County
Growing Tips for Dubuque County
Plant bulbs pointed-end up in fall, 6–8 inches deep and 6–8 inches apart in well-drained soil. Allow 12–16 weeks of cold dormancy for proper vernalization. Do not cut back foliage until it turns yellow (6–8 weeks after bloom) — the dying leaves photosynthesize energy into the bulb for next year. Lift and divide overcrowded clumps every 4–5 years in summer after foliage dies back. In zones 7b–9b, select heat-tolerant cultivars (Jonquilla, Tazetta, and Cyclamineus divisions) that perform better with less chill than large-cupped types. Zones 10+: insufficient winter cold; pre-chilling is required but results inconsistent — not recommended for outdoor culture.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Daffodils in Other Locations
Frequently Asked Questions
When should I plant Daffodils in Dubuque County, IA?
Dubuque County is in Zone 5a with an average last frost of April 29. Plan your Daffodils planting based on this frost date — see the calendar above for exact timing.
What planting zone is Dubuque County, IA?
Dubuque County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 29 and first fall frost is October 9.
When should I plant Daffodils in Dubuque County, IA?
In Dubuque County, IA, plant Daffodils 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 Dubuque County, IA for Daffodils?
Dubuque County sits in USDA Zone 5a. Daffodils grows reliably in zones 3a through 9b, so it's a good fit here.
Can Daffodils grow in Dubuque County's climate?
Yes — Daffodils grows well in Dubuque County's temperate climate. Dubuque County averages a 163-day frost-free season, with last frost around April 29 and first frost around October 9.
Your Dubuque County Garden Planner — Free
A 22-page printable planner built for Dubuque 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.