When to plant Portulaca in Greene County County,
Greene County County gardeners should plant Portulaca between May 11 and June 1 in spring. With Greene County County's Zone 5a climate (last frost April 27), Portulaca needs 70 days to mature — plant by July 27 for a full harvest.
When to Plant Portulaca in Greene County, IA
Your June gardening checklist
June is a pivotal month for Greene County, Iowa gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Time to start portulaca inside
A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.
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Collect portulaca at their peak
The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.
Get ahead of July
- First harvests: portulaca
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.
Greene County, Iowa is in USDA Zone 5a. The average last spring frost is April 27 and the first fall frost is October 5, giving you a growing season of approximately 161 days.
At an elevation of 1,292 feet, Greene County receives approximately 33.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Portulaca during the growing season.
Greene County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-6.9
Drainage
Well Drained
Portulaca Planting Risk Windows
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 Greene County
How your county's soil matches Portulaca's growing requirements.
Soil pH
Your soil pH (5.8–6.9) is within Portulaca's preferred range (5.5–7.0).
Soil Texture
The silt loam soil in Greene County is excellent for Portulaca — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.2%) — Portulaca will thrive.
How to Plant Portulaca
Succession Planting Portulaca
Sow every 5.7 weeks. Last sowing by Jul 27 to harvest before frost.
Portulaca Water Budget
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 | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.1" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.6" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2.9" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.4" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.1" | 0" | ❄️ Dormant |
| Dec | — | 2.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Greene 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 Planting Timeline — Greene County, IA
Portulaca Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 23 | Mar 23 – Apr 6 |
| Transplant Outdoors | May 11 | May 11 – May 25 |
| Direct Sow | May 11 | May 11 – Jun 1 |
| Bloom | June 29 | Jun 29 – Sep 28 |
· 8" apart · Rows 10" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Direct Sow Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | — |
| 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: ideal
🗺️ USDA Zone
Zone 5a
📆 Growing Season
161 days in Greene County
Growing Tips for Portulaca in Greene County
Direct sow Portulaca outdoors after April 27 in Greene 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 →
Portulaca in Other Locations
Frequently Asked Questions
When should I plant Portulaca in Greene County, IA?
Greene County is in Zone 5a with an average last frost of April 27. Plan your Portulaca planting based on this frost date — see the calendar above for exact timing.
What planting zone is Greene County, IA?
Greene County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 27 and first fall frost is October 5.
When should I plant Portulaca in Greene County County, ?
In Greene County County, , plant Portulaca after the last frost (around April 27) and before the first frost (around October 5). Best results when soil holds above 50°F.
What growing zone is Greene County County, for Portulaca?
Greene County County sits in USDA Zone 5a. Portulaca grows reliably in zones 3a through 11b, so it's a good fit here.
Can Portulaca grow in Greene County County's climate?
Yes — Portulaca grows well in Greene County County's temperate climate. Greene County County averages a 161-day frost-free season, with last frost around April 27 and first frost around October 5.
Your Greene County Garden Planner — Free
A 22-page printable planner built for Greene County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.