When to Plant Impatiens in Union County, OR
June in Union County, Oregon — your action list
Here's what deserves your attention in Union County, Oregon this month. Everything below is tailored to Zone 6b and timed around your local frost dates.
Coming up in July — start thinking about
- Starting indoors: impatiens
- First harvests: impatiens
Impatiens (Impatiens walleriana) are the go-to annual for shaded beds and containers. They produce a continuous carpet of flat-faced blooms from transplant until frost, needing little deadheading. Their preference for consistent moisture and part-shade makes them ideal under trees and along north-facing borders.
Union County, Oregon is in USDA Zone 6b. The average last spring frost is May 12 and the first fall frost is September 26, giving you a growing season of approximately 137 days.
At an elevation of 2,751 feet, Union County receives approximately 23.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Impatiens during the growing season.
Union County Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-6.6
Drainage
Well Drained
Impatiens 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 Union County
How your county's soil matches Impatiens's growing requirements.
Soil pH
Your soil pH (5.2–6.6) is more acidic than Impatiens prefers (6.0–6.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Union County is excellent for Impatiens — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Impatiens.
Organic Matter
Organic matter is excellent (5.6%) — Impatiens will thrive.
How to Plant Impatiens
Succession Planting Impatiens
Sow every 6.9 weeks. Last sowing by Jul 13 to harvest before frost.
Impatiens Water Budget
Monthly Watering Guide for Impatiens
Impatiens needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Impatiens Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.9" | 0" | ❄️ Dormant |
| Feb | — | 2.6" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | — | 1.5" | 0" | ❄️ Dormant |
| May | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Jun | 4.3" | 0.9" | 3.4" | 🚿 Regular watering |
| Jul | 4.3" | 0.4" | 3.9" | 🚿 Regular watering |
| Aug | 4.3" | 0.5" | 3.8" | 🚿 Regular watering |
| Sep | 4.3" | 1" | 3.3" | 🚿 Regular watering |
| Oct | — | 2" | 0" | ❄️ Dormant |
| Nov | — | 3.8" | 0" | ❄️ Dormant |
| Dec | — | 4.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Union County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Impatiens 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.
Impatiens Planting Timeline — Union County, OR
Impatiens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 17 | Mar 17 – Mar 31 |
| Transplant Outdoors | May 19 | May 19 – Jun 2 |
| Bloom | July 28 | Jul 28 – Nov 10 |
· 10" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors |
| June | Transplant Outdoors |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | Bloom |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
60–75 days
🧪 Soil pH
Needs 6–6.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 6b
📆 Growing Season
137 days in Union County
Growing Tips for Impatiens in Union County
Direct sow Impatiens outdoors after May 12 in Union County when soil has warmed and frost danger has passed.
Union County receives only 24" of rain annually. Impatiens needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 8–10 weeks before last frost at 70–75°F; germination requires light — do not cover seeds. Transplant after last frost once nights consistently exceed 50°F. Water regularly — wilting causes bud drop and they rarely fully recover the same flush. Watch for impatiens downy mildew (IDM); consider New Guinea impatiens as a resistant alternative in affected regions. Pinch tips at planting to encourage branching.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Impatiens in Other Locations
Frequently Asked Questions
When should I plant Impatiens in Union County, OR?
Union County is in Zone 6b with an average last frost of May 12. Plan your Impatiens planting based on this frost date — see the calendar above for exact timing.
What planting zone is Union County, OR?
Union County, Oregon is in USDA Hardiness Zone 6b. The average last spring frost is May 12 and first fall frost is September 26.
Your Union County Garden Planner — Free
A 22-page printable planner built for Union County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.