When to plant Calendula in Stuart, FL
For Stuart, gardeners: plant Calendula November 9 through November 30 once soil reads 50°F. A second sowing from September 6 to September 20 extends the harvest into fall.
When to Plant Calendula in Stuart, FL
Your August game plan for Martin County, Florida
If you only do a handful of things in the garden this August, make it these. They're sequenced around your zone's frost timing.
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Plant fall tomatoes & peppers
Late August is your fall transplant window. Pick heat-tolerant determinate tomatoes (Heatmaster, Solar Fire, Phoenix). They'll set fruit through fall.
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Direct-sow brassicas indoors or in shade
Broccoli, cauliflower, cabbage, Brussels sprouts germinate better in cooler conditions. Start indoors or under shade cloth, transplant in September.
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Refresh mulch & drip lines
Check drip irrigation for clogs (afternoon thunderstorm grit). Top off mulch in all beds before the cool-season crops go in.
To set up a strong September, finish these tasks
- Fall sowing: calendula
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.
Stuart, Florida is in USDA Zone 10b. The average last spring frost is January 25 and the first fall frost is December 13, giving you a growing season of approximately 322 days.
At an elevation of 80 feet, Martin County receives approximately 56.3 inches of rainfall annually with predominantly sand soil. Summer highs average 88°F, providing good warmth for Calendula during the growing season. 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.
Stuart Soil Profile
Soil Type
Sand
Soil pH
5.1-5.7
Drainage
Well Drained
Calendula Planting Risk Windows
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 Stuart
How your county's soil matches Calendula's growing requirements.
Soil pH
Your soil pH (5.1–5.7) is more acidic than Calendula prefers (5.5–7.0). Add garden lime to raise pH.
Soil Texture
Sandy soil in Martin 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 (1.5%). Add 2-3 inches of compost before planting Calendula.
How to Plant Calendula
Fall planting: Sow 14 weeks before your first frost date for a fall harvest.
Succession Planting Calendula
Sow every 5.7 weeks. Last sowing by Oct 04 to harvest before frost.
For a dedicated fall crop, sow by Sep 06.
Calendula Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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" | 2.8" | 0" | ✅ Rainfall sufficient |
| Feb | 2.2" | 3.1" | 0" | ✅ Rainfall sufficient |
| Mar | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 2.3" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3.4" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 8.6" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 7.9" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 8.4" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 8.2" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 4.2" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 2.2" | 0" | ✅ Rainfall sufficient |
| Dec | 2.2" | 2.1" | 0.1" | 💧 Light watering |
Water needs are for active growing months only (Jan–Dec in Martin 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 Planting Timeline — Stuart, FL
Calendula Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | December 7 | Dec 7 – Dec 21 |
| Direct Sow | November 9 | Nov 9 – Nov 30 |
| Bloom | January 18 | Jan 18 – Apr 26 |
| Fall Sowing | September 6 | Sep 6 – Sep 20 |
Plant 0.3" deep · 9" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Bloom |
| February | Bloom |
| March | Bloom |
| April | Bloom |
| May | — |
| June | — |
| July | — |
| August | — |
| September | Fall Sowing |
| October | — |
| November | Direct Sow |
| December | Transplant Outdoors |
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: too_acidic
🗺️ USDA Zone
Zone 10b
📆 Growing Season
322 days in Martin County
Growing Tips for Calendula in Stuart
Direct sow Calendula outdoors after January 25 in Martin County when soil has warmed and frost danger has passed.
Sandy soil in Martin County dries quickly — mulch Calendula with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
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 →
Calendula in Other Locations
When should I plant Calendula in Stuart, FL?
In Stuart, FL, plant Calendula after the last frost (around January 25) and before the first frost (around December 13). Best results when soil holds above 50°F.
What growing zone is Stuart, FL for Calendula?
Stuart sits in USDA Zone 10b. Calendula grows reliably in zones 2a through 11b, so it's a good fit here.
Can Calendula grow in Stuart's climate?
Yes — Calendula grows well in Stuart's temperate climate. Stuart averages a 323-day frost-free season, with last frost around January 25 and first frost around December 13.
Your Martin County Garden Planner — Free
A 22-page printable planner built for Martin County (Zone 10b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.