When to plant Hyacinths in Larimer County County,
For Larimer County County, gardeners: plant Hyacinths mid-spring through late spring once soil reads 50°F. A second sowing from August 25 to September 8 extends the harvest into fall.
When to Plant Hyacinths in Larimer County, CO
Top priorities for Larimer County, Colorado gardeners in June
Each item below is timed to Larimer County, Colorado's frost dates and soil temperatures. Skip nothing, stress about nothing.
Hyacinths (Hyacinthus orientalis) fill the spring garden with an almost overwhelming fragrance — a single cluster of blooms can perfume an entire yard. Dense, upright spikes of waxy florets in shades of purple, pink, blue, white, and red emerge in mid-spring, bridging the gap between the first crocus and the tulip peak. Though bulbs bloom most spectacularly in their first year, established plantings continue to produce graceful, less-dense flower spikes for several years. Deer and rabbits avoid them due to toxic alkaloids.
Larimer County, Colorado is in USDA Zone 5b. The average last spring frost is May 2 and the first fall frost is October 6, giving you a growing season of approximately 157 days.
At an elevation of 7,108 feet, Larimer County receives approximately 23.4 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Hyacinths to ensure they mature before fall.
Larimer County Soil Profile
Soil Type
Loam
Soil pH
6.4-8.2
Drainage
Well Drained
Hyacinths 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 Larimer County
How your county's soil matches Hyacinths's growing requirements.
Soil pH
Your soil pH (6.4–8.2) overlaps with Hyacinths's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Larimer County is excellent for Hyacinths — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Hyacinths.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Hyacinths.
How to Plant Hyacinths
Fall planting: Sow 6 weeks before your first frost date for a fall harvest.
Succession Planting Hyacinths
Sow every 1.6 weeks. Last sowing by Sep 08 to harvest before frost.
For a dedicated fall crop, sow by Aug 25.
Hyacinths Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Hyacinths
Hyacinths 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 | Hyacinths Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 1.3" | 0" | ❄️ Dormant |
| Mar | — | 2.1" | 0" | ❄️ Dormant |
| Apr | — | 2.2" | 0" | ❄️ Dormant |
| May | 2.2" | 2.5" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 1.9" | 0.3" | 💧 Light watering |
| Jul | 2.2" | 2.3" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 2.5" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2" | 0.2" | 💧 Light watering |
| Oct | 2.2" | 1.9" | 0.3" | 💧 Light watering |
| Nov | — | 1.7" | 0" | ❄️ Dormant |
| Dec | — | 1.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Larimer County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Hyacinths 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.
Hyacinths Planting Timeline — Larimer County, CO
Hyacinths Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Bloom | August 4 | Aug 4 – Sep 1 |
| Fall Sowing | August 25 | Aug 25 – Sep 8 |
Plant 6" deep · 6" apart · Rows 8" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | — |
| June | — |
| July | — |
| August | Fall Sowing Bloom |
| September | Fall Sowing Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Only during dry spells
📅 Days to Maturity
14–28 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 5b
📆 Growing Season
157 days in Larimer County
Growing Tips for Hyacinths in Larimer County
Direct sow Hyacinths outdoors after May 02 in Larimer County when soil has warmed and frost danger has passed.
Your generous 157.0-day season in Larimer County allows multiple plantings of Hyacinths. Sow every 7.0 days for continuous harvest.
Larimer County receives only 23" of rain annually. Hyacinths needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Plant bulbs 6 inches deep and 6 inches apart in fall, when soil drops below 60°F. Wear gloves when handling — bulb sap causes contact dermatitis in some people. After bloom, deadhead the spent spike but leave the strap-like foliage until it yellows naturally. For naturalizing, plant at 6–8 inch spacings and allow clumps to mature undisturbed. In zones 7b–9b, treat bulbs as annuals or use pre-chilled stock; performance after year 1 declines in warm-winter zones. For forcing indoors, chill bulbs 10–12 weeks then bring into warmth.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Hyacinths in Other Locations
Frequently Asked Questions
When should I plant Hyacinths in Larimer County, CO?
Larimer County is in Zone 5b with an average last frost of May 2. Plan your Hyacinths planting based on this frost date — see the calendar above for exact timing.
What planting zone is Larimer County, CO?
Larimer County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 2 and first fall frost is October 6.
When should I plant Hyacinths in Larimer County, ?
In Larimer County, , plant Hyacinths after the last frost (around May 2) and before the first frost (around October 6). Best results when soil holds above 50°F.
What growing zone is Larimer County, for Hyacinths?
Larimer County sits in USDA Zone 5b. Hyacinths grows reliably in zones 3a through 9b, so it's a good fit here.
Can Hyacinths grow in Larimer County's climate?
Yes — Hyacinths grows well in Larimer County's temperate climate. Larimer County averages a 157-day frost-free season, with last frost around May 2 and first frost around October 6.
Your Larimer County Garden Planner — Free
A 22-page printable planner built for Larimer County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.