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When to plant Geraniums in Yuma County, AZ

Yuma County sits in cold Zone 10a. Plant Geraniums December 30–January 13 for the single annual harvest; the December 1 first frost closes the window.

When to Plant Geraniums in Yuma County, AZ

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.

Yuma County, Arizona is in USDA Zone 10a. The average last spring frost is February 10 and the first fall frost is December 1, giving you a growing season of approximately 294 days.

At an elevation of 4,781 feet, Yuma County receives approximately 9.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 92°F, providing good warmth for Geraniums during the growing season. 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
Yuma County, AZ (Zone 10a) Year-round
294 days
Last Spring Frost February 10
294 growing days
First Fall Frost December 1

Yuma County Soil Profile

Soil Type

Sandy Loam

Soil pH

6.9-8.4

Drainage

Well Drained

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 0.6" 0" ❄️ Dormant
Feb 4.3" 0.5" 3.8" 🚿 Regular watering
Mar 4.3" 0.5" 3.8" 🚿 Regular watering
Apr 4.3" 0.3" 4" 🚿 Regular watering
May 4.3" 0.2" 4.1" 🚿 Regular watering
Jun 4.3" 0.3" 4" 🚿 Regular watering
Jul 4.3" 1.8" 2.5" 🚿 Regular watering
Aug 4.3" 1.9" 2.4" 🚿 Regular watering
Sep 4.3" 1.4" 2.9" 🚿 Regular watering
Oct 4.3" 0.8" 3.5" 🚿 Regular watering
Nov 4.3" 0.5" 3.8" 🚿 Regular watering
Dec 4.3" 0.6" 3.7" 🚿 Regular watering

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

Geraniums Planting Timeline — Yuma County, AZ

Geraniums Planting Calendar

Activity When Date Range
Start Indoors December 2 Dec 2 – Dec 16
Transplant Outdoors December 30 Dec 30 – Jan 13
Bloom March 10 Mar 10 – Oct 6

Plant 0.1" deep · 14" apart · Rows 16" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 10a

📆 Growing Season

294 days in Yuma County

Growing Tips for Yuma County

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 Yuma County, AZ?

Yuma County is in Zone 10a with an average last frost of February 10. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.

What planting zone is Yuma County, AZ?

Yuma County, Arizona is in USDA Hardiness Zone 10a. The average last spring frost is February 10 and first fall frost is December 1.

When should I plant Geraniums in Yuma County, AZ?

In Yuma County, AZ, plant Geraniums after the last frost (around February 10) and before the first frost (around December 1). Best results when soil holds above 50°F.

What growing zone is Yuma County, AZ for Geraniums?

Yuma County sits in USDA Zone 10a. Geraniums grows reliably in zones 2a through 11b, so it's a good fit here.

Can Geraniums grow in Yuma County's climate?

Yes — Geraniums grows well in Yuma County's temperate climate. Yuma County averages a 295-day frost-free season, with last frost around February 10 and first frost around December 1.

🌱

Your Yuma County Garden Planner — Free

A 22-page printable planner built for Yuma County (Zone 10a). 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 Yuma County, AZ. Local conditions may vary. Last updated: August 2026.

Sources & credits

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