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When to plant Alliums in Duval County County,

Alliums planted in Duval County County between mid-spring and late spring matures in 42 days — well before the November 29 first frost. A second sowing from November 8 to November 22 extends the harvest into fall.

When to Plant Alliums in Duval County, FL

Duval County, Florida Zone 9b June

This month in Duval County, Florida

If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.

Avg. last frost February 24
Avg. first frost November 29
Soil temp (4") 88°F
Watering Low
Pest pressure High
Daylight 13.9 hrs

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Ornamental alliums (Allium spp.) bridge the gap between spring and summer with their striking globe-shaped flower heads in shades of purple, violet, white, and pink. Blooming after tulips have faded, they extend the spring display well into early summer. 'Gladiator', 'Globemaster', and 'Purple Sensation' produce softball-sized heads on 18–36 inch stems, while smaller species create charming accents at border fronts. Deer and rodents shun them completely due to the characteristic onion scent. Dried seed heads provide architectural interest into fall.

Duval County, Florida is in USDA Zone 9b. The average last spring frost is February 24 and the first fall frost is November 29, giving you a growing season of approximately 278 days.

At an elevation of 337 feet, Duval County receives approximately 56.9 inches of rainfall annually with predominantly sand soil. Summer highs average 102°F, so Alliums may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Alliums will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Alliums root diseases.

Bulb Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Duval County, FL (Zone 9b) Year-round
278 days
Last Spring Frost February 24
278 growing days
First Fall Frost November 29

Duval County Soil Profile

Soil Type

Sand

Soil pH

5-5.8

Drainage

Well Drained

Alliums Planting Risk Windows

Early Start (70% safe) ✓ Fits season (234 days to spare)
Transplant: Feb 11 🌸 Bloom: Mar 11 – Apr 1
Recommended (50%) ✓ Fits season (229 days to spare)
Transplant: Feb 24 🌸 Bloom: Mar 24 – Apr 14
Safe Start (90%) ✓ Fits season (225 days to spare)
Transplant: Mar 21 🌸 Bloom: Apr 18 – May 9

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 Duval County

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

Soil pH

Your soil pH (5.0–5.8) is more acidic than Alliums prefers (5.5–7.5). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is low (1.4%). Add 2-3 inches of compost before planting Alliums.

How to Plant Alliums

5"
Planting Depth
7"
Between Plants
8"
Between Rows

Fall planting: Sow 3 weeks before your first frost date for a fall harvest.

Succession Planting Alliums

12
successive plantings in your 278-day season

Sow every 3.1 weeks. Last sowing by Oct 18 to harvest before frost.

For a dedicated fall crop, sow by Nov 08.

Alliums Water Budget

Plant needs
0.5″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Alliums

Alliums 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 Alliums Needs Rainfall You Supplement Action
Jan 2.6" 0" ❄️ Dormant
Feb 2.2" 2.8" 0" ✅ Rainfall sufficient
Mar 2.2" 3.6" 0" ✅ Rainfall sufficient
Apr 2.2" 3" 0" ✅ Rainfall sufficient
May 2.2" 3.5" 0" ✅ Rainfall sufficient
Jun 2.2" 8.7" 0" ✅ Rainfall sufficient
Jul 2.2" 7.8" 0" ✅ Rainfall sufficient
Aug 2.2" 8.9" 0" ✅ Rainfall sufficient
Sep 2.2" 6.3" 0" ✅ Rainfall sufficient
Oct 2.2" 4.7" 0" ✅ Rainfall sufficient
Nov 2.2" 2.6" 0" ✅ Rainfall sufficient
Dec 2.4" 0" ❄️ Dormant

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

Alliums 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.

Alliums needs ~928 GDD — county provides 7,393 GDD Excellent fit

Alliums Planting Timeline — Duval County, FL

Alliums Planting Calendar

Activity When Date Range
Bloom December 6 Dec 6 – Dec 27
Fall Sowing November 8 Nov 8 – Nov 22

Plant 5" deep · 7" apart · Rows 8" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April
May
June
July
August
September
October
November Fall Sowing
December Bloom

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

28–42 days

🧪 Soil pH

Needs 5.5–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9b

📆 Growing Season

278 days in Duval County

Growing Tips for Alliums in Duval County

Direct sow Alliums outdoors after February 24 in Duval County when soil has warmed and frost danger has passed.

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

With summer highs reaching 102°F in Duval County, provide afternoon shade for Alliums and water deeply in the morning.

Your generous 279.0-day season in Duval County allows multiple plantings of Alliums. Sow every 14.0 days for continuous harvest.

Common pests for Alliums in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.

General growing tips

Plant bulbs in fall, 3–4 times as deep as the bulb diameter (typically 4–6 inches for large types, 3 inches for small species). Space 6–8 inches apart for standard cultivars. Foliage often looks untidy as it dies back before bloom — plant around perennials that will conceal the yellowing leaves. Excellent drainage is essential; alliums rot in wet soils. Leave bulbs in place for naturalization; divide every 3–4 years when clusters become congested. Deadhead spent globes or leave for ornamental seedheads and self-sowing.

Companion Planting

Good Companions

Avoid Planting Near

  • Beans
  • Peas

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Alliums in Duval County, FL?

Duval County is in Zone 9b with an average last frost of February 24. Plan your Alliums planting based on this frost date — see the calendar above for exact timing.

What planting zone is Duval County, FL?

Duval County, Florida is in USDA Hardiness Zone 9b. The average last spring frost is February 24 and first fall frost is November 29.

When should I plant Alliums in Duval County County, ?

In Duval County County, , plant Alliums after the last frost (around February 24) and before the first frost (around November 29). Best results when soil holds above 50°F.

What growing zone is Duval County County, for Alliums?

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

Can Alliums grow in Duval County County's climate?

Yes — Alliums grows well in Duval County County's temperate climate. Duval County County averages a 279-day frost-free season, with last frost around February 24 and first frost around November 29.

🌱

Your Duval County Garden Planner — Free

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

Sources & credits

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