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When to Plant Portulaca in Custer County, NE

Custer County, Nebraska Zone 5b August

Your August game plan for Custer County, Nebraska

Welcome to August in Zone 5b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost May 7
Avg. first frost October 2
Soil temp (4") 75°F
Watering Low
Pest pressure High
Daylight 13.7 hrs
  1. Pick portulaca

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

Get ahead of September
  • 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, Nebraska is in USDA Zone 5b. The average last spring frost is May 7 and the first fall frost is October 2, giving you a growing season of approximately 148 days.

At an elevation of 997 feet, Custer County receives approximately 31.2 inches of rainfall annually with predominantly loam soil. Summer highs average 83°F, so choose short-season varieties of Portulaca to ensure they mature before fall.

Annual Blooms in Summer Pollinator-friendly Deer-resistant
Custer County, NE (Zone 5b) Short season
148 days
Last Spring Frost May 7
148 growing days
First Fall Frost October 2

Custer County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.6

Drainage

Well Drained

Portulaca Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 25 Transplant: May 6 🌸 Bloom: Jun 24 – Sep 30
Recommended (50%) ✗ May not fit
Start indoors: Apr 2 Transplant: May 14 🌸 Bloom: Jul 2 – Oct 8
Safe Start (90%) ✗ May not fit
Start indoors: Apr 12 Transplant: May 24 🌸 Bloom: Jul 12 – Oct 18

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 (6.2–7.6) 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 (3.9%). 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 24 to harvest before frost.

Portulaca Water Budget

Plant needs
0.5″/week
Rainfall provides
0.9″/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 0.7" 0" ❄️ Dormant
Feb 1.1" 0" ❄️ Dormant
Mar 2" 0" ❄️ Dormant
Apr 3.7" 0" ❄️ Dormant
May 2.2" 4.3" 0" ✅ Rainfall sufficient
Jun 2.2" 4.4" 0" ✅ Rainfall sufficient
Jul 2.2" 4.4" 0" ✅ Rainfall sufficient
Aug 2.2" 3.9" 0" ✅ Rainfall sufficient
Sep 2.2" 2.9" 0" ✅ Rainfall sufficient
Oct 2.2" 2.1" 0.1" 💧 Light watering
Nov 1" 0" ❄️ Dormant
Dec 0.8" 0" ❄️ Dormant

Water needs are for active growing months only (May–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 ~735 GDD — county provides 1,813 GDD Excellent fit

Portulaca Planting Timeline — Custer County, NE

Portulaca Planting Calendar

Activity When Date Range
Start Indoors April 2 Apr 2 – Apr 16
Transplant Outdoors May 14 May 14 – May 28
Direct Sow May 14 May 14 – Jun 4
Bloom July 2 Jul 2 – Oct 8

· 8" apart · Rows 10" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Start Indoors
May Transplant Outdoors Direct Sow
June 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: acceptable

🗺️ USDA Zone

Zone 5b

📆 Growing Season

148 days in Custer County

Growing Tips for Portulaca in Custer County

Direct sow Portulaca outdoors after May 07 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, NE?

Custer County is in Zone 5b with an average last frost of May 7. Plan your Portulaca planting based on this frost date — see the calendar above for exact timing.

What planting zone is Custer County, NE?

Custer County, Nebraska is in USDA Hardiness Zone 5b. The average last spring frost is May 7 and first fall frost is October 2.

🌱

Your Custer County Garden Planner — Free

A 22-page printable planner built for Custer 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 Custer County, NE. Local conditions may vary. Last updated: August 2026.

Sources & credits

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