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When to plant Portulaca in St. Clair County County,

Plant Portulaca in St. Clair County County from March 20 to April 10 in spring. St. Clair County County sits in USDA Zone 8a, with last frost around March 27 and first frost on November 1.

When to Plant Portulaca in St. Clair County, AL

St. Clair County, Alabama Zone 8a June

What to do in June

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

Avg. last frost March 27
Avg. first frost November 1
Soil temp (4") 79°F
Watering Low
Pest pressure High
Daylight 14.2 hrs
  1. Bring in the portulaca

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

To set up a strong July, 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.

St. Clair County, Alabama is in USDA Zone 8a. The average last spring frost is March 27 and the first fall frost is November 1, giving you a growing season of approximately 219 days.

At an elevation of 211 feet, St. Clair County receives approximately 48.4 inches of rainfall annually with predominantly clay loam soil. Summer highs average 89°F, providing good warmth for Portulaca during the growing season. Clay soil retains moisture well for Portulaca, but amend with compost to improve drainage and prevent root rot.

Annual Blooms in Summer Pollinator-friendly Deer-resistant
St. Clair County, AL (Zone 8a) Long season
219 days
Last Spring Frost March 27
219 growing days
First Fall Frost November 1
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St. Clair County Soil Profile

Soil Type

Clay Loam

Soil pH

5.3-6.8

Drainage

Well Drained

Portulaca Planting Risk Windows

Early Start (70% safe) ✓ Fits season (33 days to spare)
Start indoors: Feb 20 Transplant: Mar 13 🌸 Bloom: May 1 – Sep 25
Recommended (50%) ✓ Fits season (30 days to spare)
Start indoors: Feb 27 Transplant: Mar 20 🌸 Bloom: May 8 – Oct 2
Safe Start (90%) ✓ Fits season (26 days to spare)
Start indoors: Mar 18 Transplant: Apr 8 🌸 Bloom: May 27 – 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 St. Clair County

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

Soil pH

Your soil pH (5.3–6.8) overlaps with Portulaca's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Portulaca.

How to Plant Portulaca

8"
Between Plants
10"
Between Rows

Succession Planting Portulaca

5
successive plantings in your 219-day season

Sow every 5.7 weeks. Last sowing by Aug 23 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

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 3.9" 0" ❄️ Dormant
Feb 3.6" 0" ❄️ Dormant
Mar 2.2" 4.3" 0" ✅ Rainfall sufficient
Apr 2.2" 3.8" 0" ✅ Rainfall sufficient
May 2.2" 3.7" 0" ✅ Rainfall sufficient
Jun 2.2" 4.8" 0" ✅ Rainfall sufficient
Jul 2.2" 4.8" 0" ✅ Rainfall sufficient
Aug 2.2" 4.4" 0" ✅ Rainfall sufficient
Sep 2.2" 4.3" 0" ✅ Rainfall sufficient
Oct 2.2" 3.6" 0" ✅ Rainfall sufficient
Nov 2.2" 3.4" 0" ✅ Rainfall sufficient
Dec 3.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in St. Clair 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 3,668 GDD Excellent fit

Portulaca Planting Timeline — St. Clair County, AL

Portulaca Planting Calendar

Activity When Date Range
Start Indoors February 27 Feb 27 – Mar 13
Transplant Outdoors March 20 Mar 20 – Apr 3
Direct Sow March 20 Mar 20 – Apr 10
Bloom May 8 May 8 – Oct 2

· 8" apart · Rows 10" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors Transplant Outdoors Direct Sow
April Transplant Outdoors Direct Sow
May Bloom
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November
December
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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 8a

📆 Growing Season

219 days in St. Clair County

Growing Tips for Portulaca in St. Clair County

Direct sow Portulaca outdoors after March 27 in St. Clair County when soil has warmed and frost danger has passed.

With St. Clair County's clay soil (26% clay), work in 3-4 inches of compost before planting Portulaca. Avoid tilling when soil is wet to prevent compaction.

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 St. Clair County, AL?

St. Clair County is in Zone 8a with an average last frost of March 27. Plan your Portulaca planting based on this frost date — see the calendar above for exact timing.

What planting zone is St. Clair County, AL?

St. Clair County, Alabama is in USDA Hardiness Zone 8a. The average last spring frost is March 27 and first fall frost is November 1.

When should I plant Portulaca in St. Clair County County, ?

In St. Clair County County, , plant Portulaca after the last frost (around March 27) and before the first frost (around November 1). Best results when soil holds above 50°F.

What growing zone is St. Clair County County, for Portulaca?

St. Clair County County sits in USDA Zone 8a. Portulaca grows reliably in zones 3a through 11b, so it's a good fit here.

Can Portulaca grow in St. Clair County County's climate?

Yes — Portulaca grows well in St. Clair County County's temperate climate. St. Clair County County averages a 219-day frost-free season, with last frost around March 27 and first frost around November 1.

🌱

Your St. Clair County Garden Planner — Free

A 22-page printable planner built for St. Clair County (Zone 8a). 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 St. Clair County, AL. 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.