When to Plant Ageratum in Clallam County, WA
June in Clallam County, Washington — your action list
Welcome to June in Zone 8b. These are the moves that will have the biggest impact on your growing season.
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Sow ageratum in trays indoors
You're about 18 weeks out from your last frost — the perfect window to get these germinating indoors.
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Harvest ageratum as they ripen
The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.
July will be here before you know it — start on
- First harvests: ageratum
Ageratum (Ageratum houstonianum), the floss flower, produces clusters of fluffy, powder-puff blooms in the rare sky-blue and lavender tones difficult to find among warm-season annuals. Compact mounding habit makes it ideal as a front-of-border edging plant. Blooms from early summer through fall with minimal deadheading; heat and humidity tolerant once established.
Clallam County, Washington is in USDA Zone 8b. The average last spring frost is April 23 and the first fall frost is October 26, giving you a growing season of approximately 186 days.
At an elevation of 194 feet, Clallam County receives approximately 54.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Ageratum to ensure they mature before fall. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Ageratum root diseases.
Clallam County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-6.8
Drainage
Well Drained
Ageratum 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 Clallam County
How your county's soil matches Ageratum's growing requirements.
Soil pH
Your soil pH (5.7–6.8) overlaps with Ageratum's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Clallam County is excellent for Ageratum — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.8%) — Ageratum will thrive.
How to Plant Ageratum
Succession Planting Ageratum
Sow every 6.9 weeks. Last sowing by Aug 12 to harvest before frost.
Ageratum Water Budget
Monthly Watering Guide for Ageratum
Ageratum needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Ageratum Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 8.9" | 0" | ❄️ Dormant |
| Feb | — | 5.5" | 0" | ❄️ Dormant |
| Mar | — | 5.3" | 0" | ❄️ Dormant |
| Apr | 4.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 3" | 1.3" | 💧 Light watering |
| Jun | 4.3" | 2.1" | 2.2" | 🚿 Regular watering |
| Jul | 4.3" | 0.8" | 3.5" | 🚿 Regular watering |
| Aug | 4.3" | 1.1" | 3.2" | 🚿 Regular watering |
| Sep | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| Oct | 4.3" | 4" | 0.3" | 💧 Light watering |
| Nov | — | 9.1" | 0" | ❄️ Dormant |
| Dec | — | 7.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Clallam County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Ageratum 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.
Ageratum Planting Timeline — Clallam County, WA
Ageratum Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 12 | Mar 12 – Mar 26 |
| Transplant Outdoors | April 9 | Apr 9 – Apr 23 |
| Direct Sow | April 9 | Apr 9 – Apr 30 |
| Bloom | June 4 | Jun 4 – Nov 5 |
· 8" apart · Rows 10" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | Bloom |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
60–75 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
186 days in Clallam County
Growing Tips for Ageratum in Clallam County
Direct sow Ageratum outdoors after April 23 in Clallam County when soil has warmed and frost danger has passed.
Common pests for Ageratum in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 6–8 weeks before last frost — do not cover seed; it needs light to germinate. Can be direct-sown after last frost once soil warms to 60°F. Transplant or thin to proper spacing after frost danger passes. Deadheading isn't strictly required but tidying spent clusters improves appearance. Provide consistent moisture; drought causes premature setting. Avoid deep shade — blooms best in full sun to light afternoon shade.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Ageratum in Other Locations
Frequently Asked Questions
When should I plant Ageratum in Clallam County, WA?
Clallam County is in Zone 8b with an average last frost of April 23. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.
What planting zone is Clallam County, WA?
Clallam County, Washington is in USDA Hardiness Zone 8b. The average last spring frost is April 23 and first fall frost is October 26.
Your Clallam County Garden Planner — Free
A 22-page printable planner built for Clallam County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.