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When to plant Calendula in Frostproof, FL

Frostproof's climate puts the Calendula spring window between November 16 and December 7. aim for a steady week of warm soil before planting. A second sowing from September 12 to September 26 extends the harvest into fall.

When to Plant Calendula in Frostproof, FL

Polk County, Florida Zone 10a June

Your June game plan for Polk County, Florida

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

Avg. last frost January 25
Avg. first frost December 19
Soil temp (4") 89°F
Watering Low
Pest pressure High
Daylight 13.8 hrs
  1. Survive, don't thrive

    June-August is endurance gardening. Keep okra, peppers, sweet potatoes, and southern peas alive. Harvest everything daily before the heat damages produce on the vine.

  2. Start fall tomato seeds indoors

    Yes, indoors — under lights or in AC. They'll be ready to transplant in August when temperatures briefly moderate.

  3. Add compost to empty beds

    Empty beds get a thick layer of compost + mulch to suppress weeds and feed the soil for fall planting.

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Calendula (Calendula officinalis) is a cheerful, edible-flowered cool-season annual valued by herbalists, chefs, and gardeners alike. Its golden-orange petals are used in salves, teas, and as a saffron substitute. Hardy enough to tolerate light frosts, it blooms prolifically in spring and fall, taking a pause during the hottest weeks of summer.

Frostproof, Florida is in USDA Zone 10a. The average last spring frost is January 25 and the first fall frost is December 19, giving you a growing season of approximately 328 days.

At an elevation of 236 feet, Polk County receives approximately 58.3 inches of rainfall annually with predominantly sand soil. Summer highs average 96°F, so Calendula may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Calendula will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Calendula root diseases.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Frostproof, FL (Zone 10a) Year-round
328 days
Last Spring Frost January 25
328 growing days
First Fall Frost December 19

Frostproof Soil Profile

Soil Type

Sand

Soil pH

4.9-6.3

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (227 days to spare)
Transplant: Dec 8 🌸 Bloom: Jan 19 – Apr 27
Recommended (50%) ✓ Fits season (230 days to spare)
Transplant: Dec 14 🌸 Bloom: Jan 25 – May 3
Safe Start (90%) ✓ Fits season (209 days to spare)
Transplant: Jan 9 🌸 Bloom: Feb 20 – May 29

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 Frostproof

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

Soil pH

Your soil pH (4.9–6.3) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Calendula.

Organic Matter

Organic matter is low (1.6%). Add 2-3 inches of compost before planting Calendula.

How to Plant Calendula

0.3"
Planting Depth
9"
Between Plants
12"
Between Rows

Fall planting: Sow 14 weeks before your first frost date for a fall harvest.

Succession Planting Calendula

7
successive plantings in your 328-day season

Sow every 5.7 weeks. Last sowing by Oct 10 to harvest before frost.

For a dedicated fall crop, sow by Sep 12.

Calendula Water Budget

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

Monthly Watering Guide for Calendula

Calendula 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 Calendula Needs Rainfall You Supplement Action
Jan 2.2" 2.5" 0" ✅ Rainfall sufficient
Feb 2.2" 3.1" 0" ✅ Rainfall sufficient
Mar 2.2" 3.5" 0" ✅ Rainfall sufficient
Apr 2.2" 2.6" 0" ✅ Rainfall sufficient
May 2.2" 4.2" 0" ✅ Rainfall sufficient
Jun 2.2" 9" 0" ✅ Rainfall sufficient
Jul 2.2" 9.1" 0" ✅ Rainfall sufficient
Aug 2.2" 7.9" 0" ✅ Rainfall sufficient
Sep 2.2" 6.7" 0" ✅ Rainfall sufficient
Oct 2.2" 4.8" 0" ✅ Rainfall sufficient
Nov 2.2" 2.4" 0" ✅ Rainfall sufficient
Dec 2.2" 2.4" 0" ✅ Rainfall sufficient

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

Calendula 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.

Calendula needs ~1,320 GDD — county provides 7,238 GDD Excellent fit

Calendula Planting Timeline — Frostproof, FL

Calendula Planting Calendar

Activity When Date Range
Transplant Outdoors December 14 Dec 14 – Dec 28
Direct Sow November 16 Nov 16 – Dec 7
Bloom January 25 Jan 25 – May 3
Fall Sowing September 12 Sep 12 – Sep 26

Plant 0.3" deep · 9" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 10a

📆 Growing Season

328 days in Polk County

Growing Tips for Calendula in Frostproof

Direct sow Calendula outdoors after January 25 in Polk County when soil has warmed and frost danger has passed.

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

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

General growing tips

Direct-sow in early spring as soon as soil can be worked — seeds germinate in cool soil (50-65°F). In zones 7+, also sow in fall for winter/spring bloom. Deadhead consistently to extend bloom. Plants self-seed readily; save a few spent heads and allow them to drop. Harvest petals when flowers are fully open for best flavor and medicinal value.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

When should I plant Calendula in Frostproof, FL?

In Frostproof, FL, plant Calendula after the last frost (around January 25) and before the first frost (around December 19). Best results when soil holds above 50°F.

What growing zone is Frostproof, FL for Calendula?

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

Can Calendula grow in Frostproof's climate?

Yes — Calendula grows well in Frostproof's temperate climate. Frostproof averages a 329-day frost-free season, with last frost around January 25 and first frost around December 19.

🌱

Your Polk County Garden Planner — Free

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