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When to plant Geraniums in St. Lucie County County,

In St. Lucie County County, Geraniums is a single-season spring crop — there's no second fall window. Plant December 18–January 1 for an 100-day harvest, finishing well before the December 16 first frost.

When to Plant Geraniums in St. Lucie County, FL

St. Lucie County, Florida Zone 10a June

What to do in June

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

Avg. last frost January 29
Avg. first frost December 16
Soil temp (4") 89°F
Watering Low
Pest pressure High
Daylight 13.7 hrs
  1. Collect geraniums at their peak

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

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

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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.

St. Lucie County, Florida is in USDA Zone 10a. The average last spring frost is January 29 and the first fall frost is December 16, giving you a growing season of approximately 321 days.

At an elevation of 185 feet, St. Lucie County receives approximately 56.2 inches of rainfall annually with predominantly sand soil. Summer highs average 89°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. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Geraniums root diseases.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
St. Lucie County, FL (Zone 10a) Year-round
321 days
Last Spring Frost January 29
321 growing days
First Fall Frost December 16
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St. Lucie County Soil Profile

Soil Type

Sand

Soil pH

4.8-5.8

Drainage

Well Drained

Geraniums Planting Risk Windows

Early Start (70% safe) ✓ Fits season (86 days to spare)
Start indoors: Nov 10 Transplant: Dec 8 🌸 Bloom: Feb 16 – Sep 14
Recommended (50%) ✓ Fits season (83 days to spare)
Start indoors: Nov 20 Transplant: Dec 18 🌸 Bloom: Feb 26 – Sep 24
Safe Start (90%) ✓ Fits season (70 days to spare)
Start indoors: Dec 10 Transplant: Jan 7 🌸 Bloom: Mar 18 – Oct 14

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 St. Lucie County

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

Soil pH

Your soil pH (4.8–5.8) is more acidic than Geraniums prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

Sandy soil in St. Lucie 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 (1.3%). Add 2-3 inches of compost before planting Geraniums.

How to Plant Geraniums

0.1"
Planting Depth
14"
Between Plants
16"
Between Rows

Succession Planting Geraniums

5
successive plantings in your 321-day season

Sow every 8 weeks. Last sowing by Sep 07 to harvest before frost.

Geraniums Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 1,950 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — 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 4.3" 2.3" 2" 💧 Light watering
Feb 4.3" 2.7" 1.6" 💧 Light watering
Mar 4.3" 3.3" 1" 💧 Light watering
Apr 4.3" 2.2" 2.1" 💧 Light watering
May 4.3" 3.1" 1.2" 💧 Light watering
Jun 4.3" 8.1" 0" ✅ Rainfall sufficient
Jul 4.3" 9" 0" ✅ Rainfall sufficient
Aug 4.3" 8.6" 0" ✅ Rainfall sufficient
Sep 4.3" 7.5" 0" ✅ Rainfall sufficient
Oct 4.3" 5" 0" ✅ Rainfall sufficient
Nov 4.3" 2.1" 2.2" 🚿 Regular watering
Dec 4.3" 2.2" 2.1" 💧 Light watering

Water needs are for active growing months only (Jan–Dec in St. Lucie 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 ~1,424 GDD — county provides 5,393 GDD Excellent fit

Geraniums Planting Timeline — St. Lucie County, FL

Geraniums Planting Calendar

Activity When Date Range
Start Indoors November 20 Nov 20 – Dec 4
Transplant Outdoors December 18 Dec 18 – Jan 1
Bloom February 26 Feb 26 – Sep 24

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 10a

📆 Growing Season

321 days in St. Lucie County

Growing Tips for Geraniums in St. Lucie County

Direct sow Geraniums outdoors after January 29 in St. Lucie County when soil has warmed and frost danger has passed.

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

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 St. Lucie County, FL?

St. Lucie County is in Zone 10a with an average last frost of January 29. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.

What planting zone is St. Lucie County, FL?

St. Lucie County, Florida is in USDA Hardiness Zone 10a. The average last spring frost is January 29 and first fall frost is December 16.

When should I plant Geraniums in St. Lucie County, ?

In St. Lucie County, , plant Geraniums after the last frost (around January 29) and before the first frost (around December 16). Best results when soil holds above 50°F.

What growing zone is St. Lucie County, for Geraniums?

St. Lucie 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 St. Lucie County's climate?

Yes — Geraniums grows well in St. Lucie County's temperate climate. St. Lucie County averages a 322-day frost-free season, with last frost around January 29 and first frost around December 16.

🌱

Your St. Lucie County Garden Planner — Free

A 22-page printable planner built for St. Lucie 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 St. Lucie County, FL. 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.