When to Plant Pansy in Clackamas County, OR
This month in Clackamas County, Oregon
A quick June briefing for Clackamas County, Oregon gardeners — what's urgent, what's next, and what can wait.
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Indoor seed-starting week for pansy
These need a head start before your last frost (April 14). Sow into cells now so you're ready to transplant in a few weeks.
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Pick pansy
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
July prep starts now
- First harvests: pansy
Pansies (Viola × wittrockiana) are beloved cool-season annuals offering some of the widest color range in the annual garden. Their cheerful "faces" appear in early spring — or even late winter in mild climates — and hold up remarkably well through frosts. Heat causes them to go leggy and stop blooming; replace with warm-season annuals once daytime temps exceed 70°F.
Clackamas County, Oregon is in USDA Zone 9a. The average last spring frost is April 14 and the first fall frost is October 28, giving you a growing season of approximately 197 days.
At an elevation of 199 feet, Clackamas County receives approximately 53.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Pansy during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Pansy root diseases.
Clackamas County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-6.3
Drainage
Well Drained
Pansy 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 Clackamas County
How your county's soil matches Pansy's growing requirements.
Soil pH
Your soil pH (5.7–6.3) overlaps with Pansy's range (5.4–6.2), though not a perfect match.
Soil Texture
The silt loam soil in Clackamas County is excellent for Pansy — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.7%) — Pansy will thrive.
How to Plant Pansy
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Pansy
Sow every 8 weeks. Last sowing by Jul 30 to harvest before frost.
For a dedicated fall crop, sow by Aug 05.
Pansy Water Budget
Monthly Watering Guide for Pansy
Pansy needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Pansy Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 8.3" | 0" | ❄️ Dormant |
| Feb | — | 5.3" | 0" | ❄️ Dormant |
| Mar | — | 4.8" | 0" | ❄️ Dormant |
| Apr | 4.3" | 4" | 0.3" | 💧 Light watering |
| May | 4.3" | 3.3" | 1" | 💧 Light watering |
| Jun | 4.3" | 2.1" | 2.2" | 🚿 Regular watering |
| Jul | 4.3" | 0.8" | 3.5" | 🚿 Regular watering |
| Aug | 4.3" | 1" | 3.3" | 🚿 Regular watering |
| Sep | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Oct | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Nov | — | 8.2" | 0" | ❄️ Dormant |
| Dec | — | 8.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Clackamas County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Pansy 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.
Pansy Planting Timeline — Clackamas County, OR
Pansy Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 3 | Feb 3 – Feb 17 |
| Transplant Outdoors | March 17 | Mar 17 – Mar 31 |
| Bloom | May 5 | May 5 – Aug 4 |
| Fall Sowing | August 5 | Aug 5 – Aug 19 |
Plant 0.3" deep · 7" apart · Rows 10" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Transplant Outdoors |
| April | — |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | Fall Sowing Bloom |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
70–90 days
🧪 Soil pH
Needs 5.4–6.2 · Your soil: acceptable
🗺️ USDA Zone
Zone 9a
📆 Growing Season
197 days in Clackamas County
Growing Tips for Pansy in Clackamas County
Direct sow Pansy outdoors after April 14 in Clackamas County when soil has warmed and frost danger has passed.
General growing tips
Start indoors 10-12 weeks before last frost for spring transplants. In zones 6+, fall planting (8-10 weeks before first frost) gives overwintering plants that bloom earliest in spring. Plant in full sun in cool weather; afternoon shade helps extend bloom in zones 7-8. Deadhead to prevent premature seed set. Shear back by one-third when plants go leggy to extend the season.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Pansy in Other Locations
Frequently Asked Questions
When should I plant Pansy in Clackamas County, OR?
Clackamas County is in Zone 9a with an average last frost of April 14. Plan your Pansy planting based on this frost date — see the calendar above for exact timing.
What planting zone is Clackamas County, OR?
Clackamas County, Oregon is in USDA Hardiness Zone 9a. The average last spring frost is April 14 and first fall frost is October 28.
Your Clackamas County Garden Planner — Free
A 22-page printable planner built for Clackamas 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.