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When to plant Geraniums in Coconino County County,

Plant Geraniums in Coconino County County during the brief May 28–June 11 window. With 122 frost-free days, fall plantings can't mature before September 27.

When to Plant Geraniums in Coconino County, AZ

Coconino County, Arizona Zone 7a June

June in the garden — Coconino County, Arizona

A quick June briefing for Coconino County, Arizona gardeners — what's urgent, what's next, and what can wait.

Avg. last frost May 28
Avg. first frost September 27
Soil temp (4") 45°F
Watering Critical
Pest pressure High
Daylight 14.4 hrs

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Geraniums (Pelargonium × hortorum) are tender perennials grown as warm-season annuals throughout North America. Prized for their bold flower clusters, long bloom period, and tolerance of summer heat when planted in well-drained soil, they anchor window boxes, containers, and bed borders from late spring until hard frost. Zones 9b–11b can overwinter plants in the ground.

Coconino County, Arizona is in USDA Zone 7a. The average last spring frost is May 28 and the first fall frost is September 27, giving you a growing season of approximately 122 days.

At an elevation of 7,869 feet, Coconino County receives approximately 13.9 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 96°F, so Geraniums may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Geraniums will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Geraniums successfully. Mulch heavily to conserve soil moisture.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Coconino County, AZ (Zone 7a) Short season
122 days
Last Spring Frost May 28
122 growing days
First Fall Frost September 27

Coconino County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.2-8.6

Drainage

Well Drained

Geraniums Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Feb 6 Transplant: Apr 17 🌸 Bloom: Jun 26 – Oct 16
Recommended (50%) ✗ May not fit
Start indoors: Mar 19 Transplant: May 28 🌸 Bloom: Aug 6 – Nov 26
Safe Start (90%) ✗ May not fit
Start indoors: Apr 15 Transplant: Jun 24 🌸 Bloom: Sep 2 – Dec 23

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 Coconino County

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

Soil pH

Your soil pH (7.2–8.6) is more alkaline than Geraniums prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Coconino County warms quickly in spring but drains fast. Geraniums will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Geraniums.

Organic Matter

Organic matter is low (0.8%). Add 2-3 inches of compost before planting Geraniums.

How to Plant Geraniums

0.1"
Planting Depth
12"
Between Plants
14"
Between Rows

Geraniums Water Budget

Plant needs
1.0″/week
Rainfall provides
0.5″/week
You supply
1.0″/week
Watering frequency 2-3 times/week
Season total 1,070 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Geraniums

Geraniums needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Geraniums Needs Rainfall You Supplement Action
Jan 1" 0" ❄️ Dormant
Feb 0.7" 0" ❄️ Dormant
Mar 0.8" 0" ❄️ Dormant
Apr 0.4" 0" ❄️ Dormant
May 4.3" 0.3" 4" 🚿 Regular watering
Jun 4.3" 0.4" 3.9" 🚿 Regular watering
Jul 4.3" 2.6" 1.7" 💧 Light watering
Aug 4.3" 3" 1.3" 💧 Light watering
Sep 4.3" 1.7" 2.6" 🚿 Regular watering
Oct 1.3" 0" ❄️ Dormant
Nov 0.8" 0" ❄️ Dormant
Dec 0.9" 0" ❄️ Dormant

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

Geraniums 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.

Geraniums needs ~1,870 GDD — county provides 2,684 GDD Excellent fit

Geraniums Planting Timeline — Coconino County, AZ

Geraniums Planting Calendar

Activity When Date Range
Start Indoors March 19 Mar 19 – Apr 2
Transplant Outdoors May 28 May 28 – Jun 11
Bloom August 6 Aug 6 – Nov 26

Plant 0.1" deep · 12" apart · Rows 14" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 2-3 times/week

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 7a

📆 Growing Season

122 days in Coconino County

Growing Tips for Geraniums in Coconino County

Direct sow Geraniums outdoors after May 28 in Coconino County when soil has warmed and frost danger has passed.

Sandy soil in Coconino County dries quickly — mulch Geraniums with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 96°F in Coconino County, provide afternoon shade for Geraniums and water deeply in the morning.

Coconino County receives only 14" of rain annually. Geraniums needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start seeds indoors 10–12 weeks before last frost — germination is slow and erratic without bottom heat (70–75°F). Transplant after frost danger passes. Geraniums rarely direct-sown; cuttings or transplants are the standard. Deadhead spent umbels weekly to maintain continuous bloom. Let soil dry slightly between waterings to prevent root rot. In zones 10–11 plants may be left in ground year-round or overwintered as houseplants.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Geraniums in Coconino County, AZ?

Coconino County is in Zone 7a with an average last frost of May 28. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.

What planting zone is Coconino County, AZ?

Coconino County, Arizona is in USDA Hardiness Zone 7a. The average last spring frost is May 28 and first fall frost is September 27.

When should I plant Geraniums in Coconino County, ?

In Coconino County, , plant Geraniums after the last frost (around May 28) and before the first frost (around September 27). Best results when soil holds above 50°F.

What growing zone is Coconino County, for Geraniums?

Coconino County sits in USDA Zone 7a. Geraniums grows reliably in zones 2a through 11b, so it's a good fit here.

Can Geraniums grow in Coconino County's climate?

Yes — Geraniums grows well in Coconino County's temperate climate. Coconino County averages a 122-day frost-free season, with last frost around May 28 and first frost around September 27.

🌱

Your Coconino County Garden Planner — Free

A 22-page printable planner built for Coconino County (Zone 7a). 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 Coconino County, AZ. 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.