When to plant Daffodils in Cassia County, ID
In Cassia County, plant Daffodils in spring between mid-spring and late spring, once soil temps hold above 50°F. Cassia County's last frost averages May 15, so time plantings around the expected last-frost window for best survival. For a fall crop, sow between August 20 and September 3 — roughly 20–40 days before the first frost on October 1.
When to Plant Daffodils in Cassia County, ID
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.
Cassia County, Idaho is in USDA Zone 6b. The average last spring frost is May 15 and the first fall frost is October 1, giving you a growing season of approximately 139 days.
At an elevation of 8,089 feet, Cassia County receives approximately 17.5 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Daffodils during the growing season. With low rainfall, drip irrigation is essential for growing Daffodils successfully. Mulch heavily to conserve soil moisture.
Cassia County Soil Profile
Soil Type
Loam
Soil pH
6.3-8.2
Drainage
Well Drained
Monthly Watering Guide for Daffodils
Daffodils needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Daffodils Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.1" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 1.7" | 0" | ❄️ Dormant |
| Apr | — | 1.8" | 0" | ❄️ Dormant |
| May | 4.3" | 2.3" | 2" | 💧 Light watering |
| Jun | 4.3" | 1.1" | 3.2" | 🚿 Regular watering |
| Jul | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Aug | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Sep | 4.3" | 1.3" | 3" | 🚿 Regular watering |
| Oct | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Nov | — | 1.1" | 0" | ❄️ Dormant |
| Dec | — | 1.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Cassia County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Daffodils Planting Timeline — Cassia County, ID
Daffodils Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Bloom | July 16 | Jul 16 – Aug 6 |
| Fall Sowing | August 20 | Aug 20 – Sep 3 |
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 6b
📆 Growing Season
139 days in Cassia County
Growing Tips for Cassia 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 Cassia County, ID?
Cassia County is in Zone 6b with an average last frost of May 15. Plan your Daffodils planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cassia County, ID?
Cassia County, Idaho is in USDA Hardiness Zone 6b. The average last spring frost is May 15 and first fall frost is October 1.
When should I plant Daffodils in Cassia County, ID?
In Cassia County, ID, plant Daffodils after the last frost (around May 15) and before the first frost (around October 1). Best results when soil holds above 50°F.
What growing zone is Cassia County, ID for Daffodils?
Cassia County sits in USDA Zone 6b. Daffodils grows reliably in zones 3a through 9b, so it's a good fit here.
Can Daffodils grow in Cassia County's climate?
Yes — Daffodils grows well in Cassia County's temperate climate. Cassia County averages a 139-day frost-free season, with last frost around May 15 and first frost around October 1.
Your Cassia County Garden Planner — Free
A 22-page printable planner built for Cassia County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.