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When to plant Impatiens in Teller County, CO

Teller County's short 148-day growing season means one Impatiens planting between May 18 and June 1. No fall crop in Zone 5b.

When to Plant Impatiens in Teller County, CO

Teller County, Colorado Zone 5b July

Your July game plan for Teller County, Colorado

Each item below is timed to Teller County, Colorado's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost May 11
Avg. first frost October 6
Soil temp (4") 56°F
Watering High
Pest pressure High
Daylight 14.5 hrs
  1. Indoor seed-starting week for impatiens

    Label every cell. You will absolutely forget which is which otherwise.

  2. Collect impatiens at their peak

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

August prep starts now
  • First harvests: impatiens

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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.

Teller County, Colorado is in USDA Zone 5b. The average last spring frost is May 11 and the first fall frost is October 6, giving you a growing season of approximately 148 days.

At an elevation of 6,538 feet, Teller County receives approximately 19.5 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Impatiens to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Impatiens successfully. Mulch heavily to conserve soil moisture.

Annual Blooms in Summer Pollinator-friendly
Teller County, CO (Zone 5b) Short season
148 days
Last Spring Frost May 11
148 growing days
First Fall Frost October 6

Teller County Soil Profile

Soil Type

Loam

Soil pH

6.4-8.1

Drainage

Well Drained

Impatiens Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 9 Transplant: May 11 🌸 Bloom: Jul 20 – Oct 19
Recommended (50%) ✗ May not fit
Start indoors: Mar 16 Transplant: May 18 🌸 Bloom: Jul 27 – Oct 26
Safe Start (90%) ✗ May not fit
Start indoors: Apr 1 Transplant: Jun 3 🌸 Bloom: Aug 12 – Nov 11

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 Teller County

How your county's soil matches Impatiens's growing requirements.

Soil pH

Your soil pH (6.4–8.1) is more alkaline than Impatiens prefers (6.0–6.5). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Teller County is excellent for Impatiens — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.5%). Annual compost additions will help Impatiens.

How to Plant Impatiens

10"
Between Plants
12"
Between Rows

Succession Planting Impatiens

2
successive plantings in your 148-day season

Sow every 6.9 weeks. Last sowing by Jul 23 to harvest before frost.

Impatiens Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 706 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 1.3" 0" ❄️ Dormant
Feb 1.2" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 2.1" 0" ❄️ Dormant
May 4.3" 2.4" 1.9" 💧 Light watering
Jun 4.3" 1.3" 3" 🚿 Regular watering
Jul 4.3" 1.5" 2.8" 🚿 Regular watering
Aug 4.3" 1.7" 2.6" 🚿 Regular watering
Sep 4.3" 1.7" 2.6" 🚿 Regular watering
Oct 4.3" 1.9" 2.4" 🚿 Regular watering
Nov 1.3" 0" ❄️ Dormant
Dec 1.2" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Teller 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 needs ~878 GDD — county provides 1,924 GDD Excellent fit

Impatiens Planting Timeline — Teller County, CO

Impatiens Planting Calendar

Activity When Date Range
Start Indoors March 16 Mar 16 – Mar 30
Transplant Outdoors May 18 May 18 – Jun 1
Bloom July 27 Jul 27 – Oct 26

· 10" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April
May Transplant Outdoors
June Transplant Outdoors
July Bloom
August Bloom
September Bloom
October Bloom
November
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_alkaline

🗺️ USDA Zone

Zone 5b

📆 Growing Season

148 days in Teller County

Growing Tips for Impatiens in Teller County

Direct sow Impatiens outdoors after May 11 in Teller County when soil has warmed and frost danger has passed.

Teller County receives only 20" 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 →

Frequently Asked Questions

When should I plant Impatiens in Teller County, CO?

Teller County is in Zone 5b with an average last frost of May 11. Plan your Impatiens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Teller County, CO?

Teller County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 11 and first fall frost is October 6.

When should I plant Impatiens in Teller County, CO?

In Teller County, CO, plant Impatiens after the last frost (around May 11) and before the first frost (around October 6). Best results when soil holds above 50°F.

What growing zone is Teller County, CO for Impatiens?

Teller County sits in USDA Zone 5b. Impatiens grows reliably in zones 2a through 11b, so it's a good fit here.

Can Impatiens grow in Teller County's climate?

Yes — Impatiens grows well in Teller County's temperate climate. Teller County averages a 148-day frost-free season, with last frost around May 11 and first frost around October 6.

🌱

Your Teller County Garden Planner — Free

A 22-page printable planner built for Teller 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.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Teller County, CO. Local conditions may vary. Last updated: July 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.