When to plant Daffodils in Boise County, ID
The best window to plant Daffodils in Boise County, is mid-spring–late spring, when soil warms to 50°F. Last frost typically hits May 18; first frost September 27. A second sowing from August 23 to September 6 extends the harvest into fall.
When to Plant Daffodils in Boise County, ID
Your July gardening checklist
July rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Boise County, Idaho.
Before August arrives, get these ready
- Fall sowing: daffodils
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.
Boise County, Idaho is in USDA Zone 7a. The average last spring frost is May 18 and the first fall frost is September 27, giving you a growing season of approximately 132 days.
At an elevation of 8,023 feet, Boise County receives approximately 24.3 inches of rainfall annually with predominantly loam soil. Summer highs average 86°F, providing good warmth for Daffodils during the growing season.
Boise County Soil Profile
Soil Type
Loam
Soil pH
6.7-7.7
Drainage
Well Drained
Daffodils 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 Boise County
How your county's soil matches Daffodils's growing requirements.
Soil pH
Your soil pH (6.7–7.7) is more alkaline than Daffodils prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Boise County is excellent for Daffodils — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Daffodils.
How to Plant Daffodils
Fall planting: Sow 5 weeks before your first frost date for a fall harvest.
Succession Planting Daffodils
Sow every 2.3 weeks. Last sowing by Aug 18 to harvest before frost.
For a dedicated fall crop, sow by Aug 23.
Daffodils Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Daffodils
Daffodils 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 | Daffodils Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2.1" | 0" | ❄️ Dormant |
| Apr | — | 2.4" | 0" | ❄️ Dormant |
| May | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 1.9" | 0.3" | 💧 Light watering |
| Jul | 2.2" | 1.8" | 0.4" | 💧 Light watering |
| Aug | 2.2" | 2.8" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 1.7" | 0.5" | 💧 Light watering |
| Oct | — | 2.4" | 0" | ❄️ Dormant |
| Nov | — | 1.5" | 0" | ❄️ Dormant |
| Dec | — | 1.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Boise County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Daffodils 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.
Daffodils Planting Timeline — Boise County, ID
Daffodils Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Bloom | July 26 | Jul 26 – Aug 16 |
| Fall Sowing | August 23 | Aug 23 – Sep 6 |
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
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
20–40 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 7a
📆 Growing Season
132 days in Boise County
Growing Tips for Daffodils in Boise County
Direct sow Daffodils outdoors after May 18 in Boise County when soil has warmed and frost danger has passed.
Your generous 132.0-day season in Boise County allows multiple plantings of Daffodils. Sow every 10.0 days for continuous harvest.
Common pests for Daffodils in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.
Boise County receives only 24" of rain annually. Daffodils needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
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 Boise County, ID?
Boise County is in Zone 7a with an average last frost of May 18. Plan your Daffodils planting based on this frost date — see the calendar above for exact timing.
What planting zone is Boise County, ID?
Boise County, Idaho is in USDA Hardiness Zone 7a. The average last spring frost is May 18 and first fall frost is September 27.
When should I plant Daffodils in Boise County, ID?
In Boise County, ID, plant Daffodils after the last frost (around May 18) and before the first frost (around September 27). Best results when soil holds above 50°F.
What growing zone is Boise County, ID for Daffodils?
Boise County sits in USDA Zone 7a. Daffodils grows reliably in zones 3a through 9b, so it's a good fit here.
Can Daffodils grow in Boise County's climate?
Yes — Daffodils grows well in Boise County's temperate climate. Boise County averages a 132-day frost-free season, with last frost around May 18 and first frost around September 27.
Your Boise County Garden Planner — Free
A 22-page printable planner built for Boise 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.