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When to plant Portulaca in Teller County, CO

Teller County sits in cold Zone 5b. Plant Portulaca May 18–June 8 for the single annual harvest; the October 6 first frost closes the window.

When to Plant Portulaca in Teller County, CO

Teller County, Colorado Zone 5b July

This month in Teller County, Colorado

July is a pivotal month for Teller County, Colorado gardens. Focus on these tasks first and you'll set up the rest of the season for success.

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. Collect portulaca at their peak

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

To set up a strong August, finish these tasks
  • First harvests: portulaca

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Portulaca (Portulaca grandiflora), commonly called moss rose, is a succulent- stemmed annual built for hot, dry, low-fertility conditions where other flowers fail. Its silky, rose-like blooms open in full sun and close at night or on cloudy days. Excellent for slopes, rock gardens, containers, and parking-strip plantings where irrigation is limited. One of the easiest annuals for neglect- proof summer color.

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 Portulaca to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Portulaca successfully. Mulch heavily to conserve soil moisture.

Annual Blooms in Summer Pollinator-friendly Deer-resistant
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

Portulaca Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 30 Transplant: May 11 🌸 Bloom: Jun 29 – Oct 5
Recommended (50%) ✗ May not fit
Start indoors: Apr 6 Transplant: May 18 🌸 Bloom: Jul 6 – Oct 12
Safe Start (90%) ✗ May not fit
Start indoors: Apr 22 Transplant: Jun 3 🌸 Bloom: Jul 22 – Oct 28

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 Portulaca's growing requirements.

Soil pH

Your soil pH (6.4–8.1) is more alkaline than Portulaca prefers (5.5–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

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

How to Plant Portulaca

8"
Between Plants
10"
Between Rows

Succession Planting Portulaca

3
successive plantings in your 148-day season

Sow every 5.7 weeks. Last sowing by Jul 28 to harvest before frost.

Portulaca Water Budget

Plant needs
0.5″/week
Rainfall provides
0.6″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Portulaca

Portulaca needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Portulaca 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 2.2" 2.4" 0" ✅ Rainfall sufficient
Jun 2.2" 1.3" 0.9" 💧 Light watering
Jul 2.2" 1.5" 0.7" 💧 Light watering
Aug 2.2" 1.7" 0.5" 💧 Light watering
Sep 2.2" 1.7" 0.5" 💧 Light watering
Oct 2.2" 1.9" 0.3" 💧 Light 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.

Portulaca 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.

Portulaca needs ~780 GDD — county provides 1,924 GDD Excellent fit

Portulaca Planting Timeline — Teller County, CO

Portulaca Planting Calendar

Activity When Date Range
Start Indoors April 6 Apr 6 – Apr 20
Transplant Outdoors May 18 May 18 – Jun 1
Direct Sow May 18 May 18 – Jun 8
Bloom July 6 Jul 6 – Oct 12

· 8" apart · Rows 10" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 5b

📆 Growing Season

148 days in Teller County

Growing Tips for Portulaca in Teller County

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

Teller County receives only 20" of rain annually. Portulaca needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct-sow after last frost once soil warms to 65°F, or start indoors 4–6 weeks before last frost. Seed is tiny — surface sow and do not cover. Thin to proper spacing after germination. Thrives in poor, well-drained soil; rich or wet soil produces lush foliage but fewer blooms. No deadheading required — plants are self-cleaning. Double-flowered varieties hold blooms open longer in overcast conditions.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Portulaca in Teller County, CO?

Teller County is in Zone 5b with an average last frost of May 11. Plan your Portulaca 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 Portulaca in Teller County, CO?

In Teller County, CO, plant Portulaca 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 Portulaca?

Teller County sits in USDA Zone 5b. Portulaca grows reliably in zones 3a through 11b, so it's a good fit here.

Can Portulaca grow in Teller County's climate?

Yes — Portulaca 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.