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When to plant Dahlias in Mohave County County,

Plant Dahlias in Mohave County County from April 5 to April 26 in spring. Mohave County County sits in USDA Zone 9b, with last frost around April 5 and first frost on November 8.

When to Plant Dahlias in Mohave County, AZ

Mohave County, Arizona Zone 9b June

June in the garden — Mohave County, Arizona

Your Mohave County, Arizona garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.

Avg. last frost April 5
Avg. first frost November 8
Soil temp (4") 72°F
Watering Critical
Pest pressure High
Daylight 14.4 hrs
  1. Collect dahlias at their peak

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

A few tasks this June that'll pay off in July
  • First harvests: dahlias

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Dahlias (Dahlia spp.) are the undisputed stars of the late-summer and fall garden, producing an extraordinary range of flower forms — from compact pompons to dinner plate-sized blooms spanning 12 inches — in virtually every color except true blue. Blooming from midsummer until the first hard frost, a single tuber grows into a massive, flower-laden plant that can produce dozens of cut flowers per week. Modern breeding has expanded the palette and forms dramatically; the American Dahlia Society recognizes over 20 flower forms. Extremely rewarding for gardeners willing to invest in the planting, staking, and (in cold zones) annual lifting of tubers.

Mohave County, Arizona is in USDA Zone 9b. The average last spring frost is April 5 and the first fall frost is November 8, giving you a growing season of approximately 217 days.

At an elevation of 3,748 feet, Mohave County receives approximately 8.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 96°F, so Dahlias may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Dahlias will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Dahlias successfully. Mulch heavily to conserve soil moisture.

Bulb Blooms in Summer Pollinator-friendly Good for cutting
Mohave County, AZ (Zone 9b) Long season
217 days
Last Spring Frost April 5
217 growing days
First Fall Frost November 8
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Mohave County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.2-8.4

Drainage

Well Drained

Dahlias Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Mar 23 🌸 Bloom: Jun 1 – Dec 14
Recommended (50%) ✗ May not fit
Transplant: Apr 5 🌸 Bloom: Jun 14 – Dec 27
Safe Start (90%) ✓ Fits season (317 days to spare)
Transplant: Apr 17 🌸 Bloom: Jun 26 – Jan 8

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 Mohave County

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

Soil pH

Your soil pH (7.2–8.4) is more alkaline than Dahlias prefers (6.0–7.5). Add sulfur or peat moss to lower pH.

Soil Texture

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

Drainage

Drainage is adequate for Dahlias.

Organic Matter

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

How to Plant Dahlias

5"
Planting Depth
18"
Between Plants
24"
Between Rows

Succession Planting Dahlias

3
successive plantings in your 217-day season

Sow every 8 weeks. Last sowing by Jul 11 to harvest before frost.

Dahlias Water Budget

Plant needs
1.0″/week
Rainfall provides
0.2″/week
You supply
1.4″/week
Watering frequency 2-3 times/week
Season total 2,645 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Dahlias

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

Month Dahlias Needs Rainfall You Supplement Action
Jan 0.6" 0" ❄️ Dormant
Feb 0.4" 0" ❄️ Dormant
Mar 0.4" 0" ❄️ Dormant
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" 1.5" 2.8" 🚿 Regular watering
Aug 4.3" 1.6" 2.7" 🚿 Regular watering
Sep 4.3" 1" 3.3" 🚿 Regular watering
Oct 4.3" 0.8" 3.5" 🚿 Regular watering
Nov 4.3" 0.4" 3.9" 🚿 Regular watering
Dec 0.6" 0" ❄️ Dormant

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

Dahlias 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.

Dahlias needs ~2,090 GDD — county provides 4,774 GDD Excellent fit

Dahlias Planting Timeline — Mohave County, AZ

Dahlias Planting Calendar

Activity When Date Range
Transplant Outdoors April 5 Apr 5 – Apr 19
Direct Sow April 5 Apr 5 – Apr 26
Bloom June 14 Jun 14 – Dec 27

Plant 5" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Transplant Outdoors Direct Sow
May
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November Bloom
December Bloom
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 2-3 times/week

📅 Days to Maturity

70–120 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 9b

📆 Growing Season

217 days in Mohave County

Growing Tips for Dahlias in Mohave County

Direct sow Dahlias outdoors after April 05 in Mohave County when soil has warmed and frost danger has passed.

Sandy soil in Mohave County dries quickly — mulch Dahlias 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 Mohave County, provide afternoon shade for Dahlias and water deeply in the morning.

Common pests for Dahlias in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

Mohave County receives only 8" of rain annually. Dahlias needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Plant tubers after all danger of frost has passed and soil temperature reaches 60°F — typically 1–2 weeks after last frost in most zones. Lay tubers horizontally 4–6 inches deep with the eye (growth point) facing up. Do not water until sprouts emerge; wet soil rots dormant tubers. Stake tall varieties (over 3 feet) at planting time to avoid root disturbance later. Pinch growing tips at 12–16 inches to encourage branching and more blooms. Deadhead regularly to extend the blooming season. In zones 8b and warmer, tubers can overwinter in the ground with a layer of mulch. In zones 3–8a, lift tubers after the first killing frost, cure for a week, and store in slightly damp vermiculite or peat at 40–50°F until spring. Divide tubers every year or two; each division must have an eye (bud) to grow.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Dahlias in Mohave County, AZ?

Mohave County is in Zone 9b with an average last frost of April 5. Plan your Dahlias planting based on this frost date — see the calendar above for exact timing.

What planting zone is Mohave County, AZ?

Mohave County, Arizona is in USDA Hardiness Zone 9b. The average last spring frost is April 5 and first fall frost is November 8.

When should I plant Dahlias in Mohave County County, ?

In Mohave County County, , plant Dahlias after the last frost (around April 5) and before the first frost (around November 8). Best results when soil holds above 50°F.

What growing zone is Mohave County County, for Dahlias?

Mohave County County sits in USDA Zone 9b. Dahlias grows reliably in zones 3a through 10b, so it's a good fit here.

Can Dahlias grow in Mohave County County's climate?

Yes — Dahlias grows well in Mohave County County's temperate climate. Mohave County County averages a 217-day frost-free season, with last frost around April 5 and first frost around November 8.

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Your Mohave County Garden Planner — Free

A 22-page printable planner built for Mohave County (Zone 9b). 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 Mohave County, AZ. Local conditions may vary. Last updated: June 2026.

Sources & credits

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