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When to plant Sedum (Stonecrop) in Larimer County, CO

In Larimer County, Sedum (Stonecrop) is a spring-only crop. Plant May 16–May 30 once soil hits 50°F.

When to Plant Sedum (Stonecrop) in Larimer County, CO

Larimer County, Colorado Zone 5b June

June to-do list for Larimer County, Colorado

June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Larimer County, Colorado.

Avg. last frost May 2
Avg. first frost October 6
Soil temp (4") 50°F
Watering High
Pest pressure High
Daylight 14.9 hrs
July prep starts now
  • Starting indoors: sedum (stonecrop)

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Sedum (Hylotelephium spectabile, formerly Sedum spectabile) is a supremely tough, drought-tolerant perennial prized for its late-season interest. The flat-topped clusters of starry flowers open pink in late summer and deepen to copper-red as temperatures cool, remaining attractive well into fall and providing seed heads that feed birds through winter. Succulent foliage emerges blue-green in spring, is handsome all season, and turns bronzy after frost. Remarkably adaptable — thrives in poor, gravelly, or sandy soils where other perennials struggle — and virtually maintenance-free once established.

Larimer County, Colorado is in USDA Zone 5b. The average last spring frost is May 2 and the first fall frost is October 6, giving you a growing season of approximately 157 days.

At an elevation of 7,108 feet, Larimer County receives approximately 23.4 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Sedum (Stonecrop) to ensure they mature before fall.

Perennial Blooms in Fall Pollinator-friendly Deer-resistant Good for cutting
Larimer County, CO (Zone 5b) Moderate season
157 days
Last Spring Frost May 2
157 growing days
First Fall Frost October 6

Larimer County Soil Profile

Soil Type

Loam

Soil pH

6.4-8.2

Drainage

Well Drained

Sedum (Stonecrop) Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Feb 24 Transplant: May 12 🌸 Bloom: Sep 8 – Nov 17
Recommended (50%) ✗ May not fit
Start indoors: Feb 28 Transplant: May 16 🌸 Bloom: Sep 12 – Nov 21
Safe Start (90%) ✗ May not fit
Start indoors: Mar 19 Transplant: Jun 4 🌸 Bloom: Oct 1 – Dec 10

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 Larimer County

How your county's soil matches Sedum (Stonecrop)'s growing requirements.

Soil pH

Your soil pH (6.4–8.2) is more alkaline than Sedum (Stonecrop) prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Larimer County is excellent for Sedum (Stonecrop) — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Sedum (Stonecrop).

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Sedum (Stonecrop).

How to Plant Sedum (Stonecrop)

1"
Planting Depth
18"
Between Plants
24"
Between Rows

Succession Planting Sedum (Stonecrop)

3
successive plantings in your 157-day season

Sow every 6.9 weeks. Last sowing by Jul 08 to harvest before frost.

Sedum (Stonecrop) Water Budget

Plant needs
0.5″/week
Rainfall provides
0.6″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 40 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Sedum (Stonecrop)

Sedum (Stonecrop) 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 Sedum (Stonecrop) Needs Rainfall You Supplement Action
Jan 1.7" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 2.1" 0" ❄️ Dormant
Apr 2.2" 0" ❄️ Dormant
May 2.2" 2.5" 0" ✅ Rainfall sufficient
Jun 2.2" 1.9" 0.3" 💧 Light watering
Jul 2.2" 2.3" 0" ✅ Rainfall sufficient
Aug 2.2" 2.5" 0" ✅ Rainfall sufficient
Sep 2.2" 2" 0.2" 💧 Light watering
Oct 2.2" 1.9" 0.3" 💧 Light watering
Nov 1.7" 0" ❄️ Dormant
Dec 1.3" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Larimer County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Sedum (Stonecrop) 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.

Sedum (Stonecrop) needs ~975 GDD — county provides 2,041 GDD Excellent fit

Sedum (Stonecrop) Planting Timeline — Larimer County, CO

Sedum (Stonecrop) Planting Calendar

Activity When Date Range
Start Indoors February 28 Feb 28 – Mar 14
Transplant Outdoors May 16 May 16 – May 30
Bloom September 12 Sep 12 – Nov 21

Plant 1" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Only during dry spells

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 5b

📆 Growing Season

157 days in Larimer County

Growing Tips for Sedum (Stonecrop) in Larimer County

Direct sow Sedum (Stonecrop) outdoors after May 02 in Larimer County when soil has warmed and frost danger has passed.

Larimer County receives only 23" of rain annually. Sedum (Stonecrop) needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Plant divisions or container plants in spring after frost danger passes, or in early fall. Excellent drainage is the primary requirement — upright border sedums will rot in wet, heavy soils over winter. Lean soil actually improves performance; avoid over-fertilizing which causes floppy stems. Tall cultivars (Autumn Joy, Matrona) may need light staking in rich soil. Divide every 3–4 years in spring when centers become sparse. Deadhead selectively — leaving seed heads through winter extends ornamental interest and feeds goldfinches. Very low water requirement once established. Year 2+ plants reach full clump size and peak bloom display.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sedum (Stonecrop) in Larimer County, CO?

Larimer County is in Zone 5b with an average last frost of May 2. Plan your Sedum (Stonecrop) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Larimer County, CO?

Larimer County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 2 and first fall frost is October 6.

When should I plant Sedum (Stonecrop) in Larimer County, CO?

In Larimer County, CO, plant Sedum (Stonecrop) after the last frost (around May 2) and before the first frost (around October 6). Best results when soil holds above 50°F.

What growing zone is Larimer County, CO for Sedum (Stonecrop)?

Larimer County sits in USDA Zone 5b. Sedum (Stonecrop) grows reliably in zones 3a through 10b, so it's a good fit here.

Can Sedum (Stonecrop) grow in Larimer County's climate?

Yes — Sedum (Stonecrop) grows well in Larimer County's temperate climate. Larimer County averages a 157-day frost-free season, with last frost around May 2 and first frost around October 6.

🌱

Your Larimer County Garden Planner — Free

A 22-page printable planner built for Larimer 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 Larimer County, CO. Local conditions may vary. Last updated: June 2026.

Sources & credits

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