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When to plant Portulaca in New Haven County County,

For Portulaca in New Haven County County, the safe spring window opens around April 30 and closes around May 21. Last expected frost is April 23, first fall frost October 19, giving a 179-day growing season.

When to Plant Portulaca in New Haven County, CT

New Haven County, Connecticut Zone 6b June

New Haven County, Connecticut gardeners: here's your June plan

Each item below is timed to New Haven County, Connecticut's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 23
Avg. first frost October 19
Soil temp (4") 72°F
Watering Low
Pest pressure High
Daylight 15 hrs
  1. Pick 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.

New Haven County, Connecticut is in USDA Zone 6b. The average last spring frost is April 23 and the first fall frost is October 19, giving you a growing season of approximately 179 days.

At an elevation of 509 feet, New Haven County receives approximately 49.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Portulaca during the growing season.

Annual Blooms in Summer Pollinator-friendly Deer-resistant
New Haven County, CT (Zone 6b) Moderate season
179 days
Last Spring Frost April 23
179 growing days
First Fall Frost October 19
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New Haven County Soil Profile

Soil Type

Silt Loam

Soil pH

5-6.5

Drainage

Well Drained

Portulaca Planting Risk Windows

Early Start (70% safe) ✓ Fits season (16 days to spare)
Start indoors: Mar 10 Transplant: Apr 21 🌸 Bloom: Jun 9 – Sep 29
Recommended (50%) ✓ Fits season (11 days to spare)
Start indoors: Mar 19 Transplant: Apr 30 🌸 Bloom: Jun 18 – Oct 8
Safe Start (90%) ✓ Fits season (2 days to spare)
Start indoors: Apr 11 Transplant: May 23 🌸 Bloom: Jul 11 – Oct 31

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 New Haven County

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

Soil pH

Your soil pH (5.0–6.5) overlaps with Portulaca's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.1%). Annual compost additions will help Portulaca.

How to Plant Portulaca

8"
Between Plants
10"
Between Rows

Succession Planting Portulaca

4
successive plantings in your 179-day season

Sow every 5.7 weeks. Last sowing by Aug 10 to harvest before frost.

Portulaca Water Budget

Plant needs
0.5″/week
Rainfall provides
1.2″/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 3.5" 0" ❄️ Dormant
Feb 3.4" 0" ❄️ Dormant
Mar 4.1" 0" ❄️ Dormant
Apr 2.2" 4.2" 0" ✅ Rainfall sufficient
May 2.2" 4.5" 0" ✅ Rainfall sufficient
Jun 2.2" 4.1" 0" ✅ Rainfall sufficient
Jul 2.2" 5.2" 0" ✅ Rainfall sufficient
Aug 2.2" 4.4" 0" ✅ Rainfall sufficient
Sep 2.2" 3.6" 0" ✅ Rainfall sufficient
Oct 2.2" 4.2" 0" ✅ Rainfall sufficient
Nov 4.2" 0" ❄️ Dormant
Dec 4" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in New Haven 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 2,998 GDD Excellent fit

Portulaca Planting Timeline — New Haven County, CT

Portulaca Planting Calendar

Activity When Date Range
Start Indoors March 19 Mar 19 – Apr 2
Transplant Outdoors April 30 Apr 30 – May 14
Direct Sow April 30 Apr 30 – May 21
Bloom June 18 Jun 18 – Oct 8

· 8" apart · Rows 10" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
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 6b

📆 Growing Season

179 days in New Haven County

Growing Tips for Portulaca in New Haven County

Direct sow Portulaca outdoors after April 23 in New Haven 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 New Haven County, CT?

New Haven County is in Zone 6b with an average last frost of April 23. Plan your Portulaca planting based on this frost date — see the calendar above for exact timing.

What planting zone is New Haven County, CT?

New Haven County, Connecticut is in USDA Hardiness Zone 6b. The average last spring frost is April 23 and first fall frost is October 19.

When should I plant Portulaca in New Haven County County, ?

In New Haven County County, , plant Portulaca after the last frost (around April 23) and before the first frost (around October 19). Best results when soil holds above 50°F.

What growing zone is New Haven County County, for Portulaca?

New Haven County County sits in USDA Zone 6b. Portulaca grows reliably in zones 3a through 11b, so it's a good fit here.

Can Portulaca grow in New Haven County County's climate?

Yes — Portulaca grows well in New Haven County County's temperate climate. New Haven County County averages a 179-day frost-free season, with last frost around April 23 and first frost around October 19.

🌱

Your New Haven County Garden Planner — Free

A 22-page printable planner built for New Haven County (Zone 6b). 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 New Haven County, CT. Local conditions may vary. Last updated: June 2026.

Sources & credits

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