Blog

When to Plant Marjoram in St. Lucie County, FL

Sweet marjoram is a tender perennial herb with a delicate, sweet oregano-like flavor. It is a cornerstone of Mediterranean cooking and pairs well with meats and vegetables.

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 89ยฐF, providing good warmth for Marjoram during the growing season. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Marjoram will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Marjoram root diseases.

St. Lucie County, FL (Zone 10a) Year-round
321 days
Last Spring Frost January 29
321 growing days
First Fall Frost December 16

St. Lucie County Soil Profile

Soil Type

Sand

Soil pH

4.8-5.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (184 days to spare)
Transplant: Jan 26 🍅 Harvest: Mar 30 – Jun 8
Recommended (50%) ✓ Fits season (181 days to spare)
Transplant: Feb 5 🍅 Harvest: Apr 9 – Jun 18
Safe Start (90%) ✓ Fits season (168 days to spare)
Transplant: Feb 25 🍅 Harvest: Apr 29 – Jul 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.

Plant 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 โ€” consider drought-tolerant varieties and mulching

Marjoram needs ~1,256 GDD — county provides 5,393 GDD Excellent fit

Marjoram Planting Timeline โ€” St. Lucie County, FL

Marjoram Planting Calendar

Activity When Date Range
Transplant Outdoors February 5 Feb 5 โ€“ Feb 19
Harvest April 9 Apr 9 โ€“ Jun 18

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February Transplant Outdoors
March โ€”
April Harvest
May Harvest
June Harvest
July โ€”
August โ€”
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

60โ€“90 days

Soil pH

6.5 โ€“ 7.5

USDA Zone

Zone 10a

Growing Season

321 days

Growing Tips for St. Lucie County

Start seeds indoors 6-8 weeks before last frost. Harvest stems just as flower buds appear for peak flavor. In cold climates, grow as an annual or bring containers indoors.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Marjoram in St. Lucie County, FL?

St. Lucie County is in Zone 10a with an average last frost of January 29. Plan your Marjoram planting based on this frost date โ€” 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.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help St. Lucie County gardeners in Zone 10a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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: April 2026.