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When to Plant Portulaca in Custer County, OK

Custer County, Oklahoma Zone 7b June

This month in Custer County, Oklahoma

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

Avg. last frost April 8
Avg. first frost October 31
Soil temp (4") 79°F
Watering Low
Pest pressure High
Daylight 14.4 hrs
  1. Harvest portulaca as they ripen

    If you can't use it all right away, check the food-preservation section of your planner.

Looking ahead to July
  • 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.

Custer County, Oklahoma is in USDA Zone 7b. The average last spring frost is April 8 and the first fall frost is October 31, giving you a growing season of approximately 206 days.

At an elevation of 767 feet, Custer County receives approximately 31.6 inches of rainfall annually with predominantly loam soil. Summer highs average 89°F, providing good warmth for Portulaca during the growing season.

Annual Blooms in Summer Pollinator-friendly Deer-resistant
Custer County, OK (Zone 7b) Long season
206 days
Last Spring Frost April 8
206 growing days
First Fall Frost October 31

Custer County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.2

Drainage

Well Drained

Portulaca Planting Risk Windows

Early Start (70% safe) ✓ Fits season (22 days to spare)
Start indoors: Mar 6 Transplant: Apr 3 🌸 Bloom: May 22 – Oct 2
Recommended (50%) ✓ Fits season (24 days to spare)
Start indoors: Mar 11 Transplant: Apr 8 🌸 Bloom: May 27 – Oct 7
Safe Start (90%) ✓ Fits season (30 days to spare)
Start indoors: Mar 21 Transplant: Apr 18 🌸 Bloom: Jun 6 – Oct 17

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 Custer County

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

Soil pH

Your soil pH (6.5–7.2) overlaps with Portulaca's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.7%). Annual compost additions will help Portulaca.

How to Plant Portulaca

8"
Between Plants
10"
Between Rows

Succession Planting Portulaca

4
successive plantings in your 206-day season

Sow every 5.7 weeks. Last sowing by Aug 22 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 0.8" 0" ❄️ Dormant
Feb 1.1" 0" ❄️ Dormant
Mar 2.1" 0" ❄️ Dormant
Apr 2.2" 3.7" 0" ✅ Rainfall sufficient
May 2.2" 4" 0" ✅ Rainfall sufficient
Jun 2.2" 5.4" 0" ✅ Rainfall sufficient
Jul 2.2" 3.7" 0" ✅ Rainfall sufficient
Aug 2.2" 4.2" 0" ✅ Rainfall sufficient
Sep 2.2" 2.7" 0" ✅ Rainfall sufficient
Oct 2.2" 1.9" 0.3" 💧 Light watering
Nov 1.1" 0" ❄️ Dormant
Dec 0.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Custer 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 ~1,005 GDD — county provides 3,450 GDD Excellent fit

Portulaca Planting Timeline — Custer County, OK

Portulaca Planting Calendar

Activity When Date Range
Start Indoors March 11 Mar 11 – Mar 25
Transplant Outdoors April 8 Apr 8 – Apr 22
Direct Sow April 8 Apr 8 – Apr 29
Bloom May 27 May 27 – Oct 7

· 8" apart · Rows 10" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Transplant Outdoors 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

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7b

📆 Growing Season

206 days in Custer County

Growing Tips for Portulaca in Custer County

Direct sow Portulaca outdoors after April 08 in Custer County when soil has warmed and frost danger has passed.

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 Custer County, OK?

Custer County is in Zone 7b with an average last frost of April 8. Plan your Portulaca planting based on this frost date — see the calendar above for exact timing.

What planting zone is Custer County, OK?

Custer County, Oklahoma is in USDA Hardiness Zone 7b. The average last spring frost is April 8 and first fall frost is October 31.

🌱

Your Custer County Garden Planner — Free

A 22-page printable planner built for Custer County (Zone 7b). 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 Custer County, OK. Local conditions may vary. Last updated: June 2026.

Sources & credits

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