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When to Plant Portulaca in Cameron County, TX

Cameron County, Texas Zone 10a August

August to-do list for Cameron County, Texas

Your Cameron County, Texas garden is entering a new phase. Here's what's on the schedule for August and why each task matters now.

Avg. last frost February 4
Avg. first frost December 22
Soil temp (4") 86°F
Watering Low
Pest pressure High
Daylight 12.9 hrs
  1. It's harvest week for portulaca

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

Coming up in September — start thinking about
  • 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.

Cameron County, Texas is in USDA Zone 10a. The average last spring frost is February 4 and the first fall frost is December 22, giving you a growing season of approximately 321 days.

At an elevation of 4,025 feet, Cameron County receives approximately 58.6 inches of rainfall annually with predominantly loam soil. Summer highs average 103°F, so Portulaca may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Portulaca root diseases.

Annual Blooms in Summer Pollinator-friendly Deer-resistant
Cameron County, TX (Zone 10a) Year-round
321 days
Last Spring Frost February 4
321 growing days
First Fall Frost December 22

Cameron County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.8

Drainage

Well Drained

Portulaca Planting Risk Windows

Early Start (70% safe) ✓ Fits season (102 days to spare)
Start indoors: Dec 20 Transplant: Dec 13 🌸 Bloom: Jan 31 – Sep 5
Recommended (50%) ✓ Fits season (90 days to spare)
Start indoors: Jan 7 Transplant: Dec 31 🌸 Bloom: Feb 18 – Sep 23
Safe Start (90%) ✓ Fits season (67 days to spare)
Start indoors: Feb 4 Transplant: Jan 28 🌸 Bloom: Mar 18 – Oct 21

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 Cameron County

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

Soil pH

Your soil pH (6.7–7.8) is more alkaline than Portulaca prefers (5.5–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Portulaca.

How to Plant Portulaca

8"
Between Plants
10"
Between Rows

Succession Planting Portulaca

7
successive plantings in your 321-day season

Sow every 5.7 weeks. Last sowing by Oct 13 to harvest before frost.

Portulaca Water Budget

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

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 1.6" 0" ❄️ Dormant
Feb 2.2" 2.2" 0" ✅ Rainfall sufficient
Mar 2.2" 3.1" 0" ✅ Rainfall sufficient
Apr 2.2" 6.1" 0" ✅ Rainfall sufficient
May 2.2" 9.2" 0" ✅ Rainfall sufficient
Jun 2.2" 9.1" 0" ✅ Rainfall sufficient
Jul 2.2" 7.5" 0" ✅ Rainfall sufficient
Aug 2.2" 6.9" 0" ✅ Rainfall sufficient
Sep 2.2" 5.6" 0" ✅ Rainfall sufficient
Oct 2.2" 3.8" 0" ✅ Rainfall sufficient
Nov 2.2" 2.1" 0.1" 💧 Light watering
Dec 2.2" 1.4" 0.8" 💧 Light watering

Water needs are for active growing months only (Feb–Dec in Cameron 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 ~1,635 GDD — county provides 8,774 GDD Excellent fit

Portulaca Planting Timeline — Cameron County, TX

Portulaca Planting Calendar

Activity When Date Range
Start Indoors January 7 Jan 7 – Jan 21
Transplant Outdoors December 31 Dec 31 – Jan 14
Direct Sow December 31 Dec 31 – Jan 21
Bloom February 18 Feb 18 – Sep 23

· 8" apart · Rows 10" apart

Month-by-Month Timeline

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

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 10a

📆 Growing Season

321 days in Cameron County

Growing Tips for Portulaca in Cameron County

Direct sow Portulaca outdoors after February 04 in Cameron County when soil has warmed and frost danger has passed.

With summer highs reaching 103°F in Cameron County, provide afternoon shade for Portulaca and water deeply in the morning.

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 Cameron County, TX?

Cameron County is in Zone 10a with an average last frost of February 4. Plan your Portulaca planting based on this frost date — see the calendar above for exact timing.

What planting zone is Cameron County, TX?

Cameron County, Texas is in USDA Hardiness Zone 10a. The average last spring frost is February 4 and first fall frost is December 22.

🌱

Your Cameron County Garden Planner — Free

A 22-page printable planner built for Cameron County (Zone 10a). 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 Cameron County, TX. 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.