When to Plant Ageratum in Kitsap County, WA
July in the garden — Kitsap County, Washington
Each item below is timed to Kitsap County, Washington's frost dates and soil temperatures. Skip nothing, stress about nothing.
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Collect ageratum at their peak
This is the payoff month. Bring a basket, bring a friend, and get into the beds.
Get ahead of August
- 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.
Kitsap County, Washington is in USDA Zone 9a. The average last spring frost is March 25 and the first fall frost is November 5, giving you a growing season of approximately 225 days.
At an elevation of 264 feet, Kitsap County receives approximately 38 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Ageratum during the growing season.
Kitsap County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-6.3
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 Kitsap County
How your county's soil matches Ageratum's growing requirements.
Soil pH
Your soil pH (5.3–6.3) is more acidic than Ageratum prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Kitsap County is excellent for Ageratum — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.5%) — Ageratum will thrive.
How to Plant Ageratum
Succession Planting Ageratum
Sow every 6.9 weeks. Last sowing by Aug 22 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 | — | 5.1" | 0" | ❄️ Dormant |
| Feb | — | 4.5" | 0" | ❄️ Dormant |
| Mar | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| May | 4.3" | 2" | 2.3" | 🚿 Regular watering |
| Jun | 4.3" | 1.3" | 3" | 🚿 Regular watering |
| Jul | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Aug | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Sep | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Oct | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Nov | 4.3" | 6.5" | 0" | ✅ Rainfall sufficient |
| Dec | — | 6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Kitsap 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 — Kitsap County, WA
Ageratum Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 11 | Feb 11 – Feb 25 |
| Transplant Outdoors | March 11 | Mar 11 – Mar 25 |
| Direct Sow | March 11 | Mar 11 – Apr 1 |
| Bloom | May 6 | May 6 – Oct 21 |
· 8" apart · Rows 10" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Transplant Outdoors Direct Sow |
| April | Direct Sow |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
60–75 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 9a
📆 Growing Season
225 days in Kitsap County
Growing Tips for Ageratum in Kitsap County
Direct sow Ageratum outdoors after March 25 in Kitsap 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 Kitsap County, WA?
Kitsap County is in Zone 9a with an average last frost of March 25. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.
What planting zone is Kitsap County, WA?
Kitsap County, Washington is in USDA Hardiness Zone 9a. The average last spring frost is March 25 and first fall frost is November 5.
Your Kitsap County Garden Planner — Free
A 22-page printable planner built for Kitsap County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.