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When to plant Sweet Alyssum in Putnam County County,

Plant Sweet Alyssum in Putnam County County from December 8 to December 29 in spring. Putnam County County sits in USDA Zone 9b, with last frost around February 9 and first frost on December 2. A second sowing from September 23 to October 7 extends the harvest into fall.

When to Plant Sweet Alyssum in Putnam County, FL

Putnam County, Florida Zone 9b June

June in Putnam County, Florida — your action list

Here's what deserves your attention in Putnam County, Florida this month. Everything below is tailored to Zone 9b and timed around your local frost dates.

Avg. last frost February 9
Avg. first frost December 2
Soil temp (4") 87°F
Watering Low
Pest pressure High
Daylight 13.9 hrs

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Sweet Alyssum (Lobularia maritima) is a low-growing cool-season annual prized for its honey-scented clusters of tiny white, pink, or purple flowers. A workhorse border plant, it tolerates light frost, self-seeds readily, and attracts beneficial insects throughout its bloom season. In warm climates it often re-blooms in fall after summer heat fades.

Putnam County, Florida is in USDA Zone 9b. The average last spring frost is February 9 and the first fall frost is December 2, giving you a growing season of approximately 296 days.

At an elevation of 278 feet, Putnam County receives approximately 57.5 inches of rainfall annually with predominantly sand soil. Summer highs average 95°F, so Sweet Alyssum may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Sweet Alyssum will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sweet Alyssum root diseases.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Fragrant
Putnam County, FL (Zone 9b) Year-round
296 days
Last Spring Frost February 9
296 growing days
First Fall Frost December 2

Putnam County Soil Profile

Soil Type

Sand

Soil pH

4.9-6.2

Drainage

Well Drained

Sweet Alyssum Planting Risk Windows

Early Start (70% safe) ✓ Fits season (213 days to spare)
Transplant: Dec 21 🌸 Bloom: Jan 25 – Apr 26
Recommended (50%) ✓ Fits season (205 days to spare)
Transplant: Jan 5 🌸 Bloom: Feb 9 – May 11
Safe Start (90%) ✓ Fits season (206 days to spare)
Transplant: Jan 28 🌸 Bloom: Mar 4 – Jun 3

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 Putnam County

How your county's soil matches Sweet Alyssum's growing requirements.

Soil pH

Your soil pH (4.9–6.2) is more acidic than Sweet Alyssum prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Sweet Alyssum.

Organic Matter

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

How to Plant Sweet Alyssum

6"
Between Plants
8"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Sweet Alyssum

7
successive plantings in your 296-day season

Sow every 5.1 weeks. Last sowing by Oct 03 to harvest before frost.

For a dedicated fall crop, sow by Sep 23.

Sweet Alyssum Water Budget

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

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Sweet Alyssum

Sweet Alyssum 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 Sweet Alyssum Needs Rainfall You Supplement Action
Jan 2.4" 0" ❄️ Dormant
Feb 2.2" 2.6" 0" ✅ Rainfall sufficient
Mar 2.2" 3.5" 0" ✅ Rainfall sufficient
Apr 2.2" 2.3" 0" ✅ Rainfall sufficient
May 2.2" 3.3" 0" ✅ Rainfall sufficient
Jun 2.2" 7.9" 0" ✅ Rainfall sufficient
Jul 2.2" 9.4" 0" ✅ Rainfall sufficient
Aug 2.2" 8.7" 0" ✅ Rainfall sufficient
Sep 2.2" 7.4" 0" ✅ Rainfall sufficient
Oct 2.2" 5.3" 0" ✅ Rainfall sufficient
Nov 2.2" 2.2" 0" ✅ Rainfall sufficient
Dec 2.2" 2.6" 0" ✅ Rainfall sufficient

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

Sweet Alyssum 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.

Sweet Alyssum needs ~1,116 GDD — county provides 6,311 GDD Excellent fit

Sweet Alyssum Planting Timeline — Putnam County, FL

Sweet Alyssum Planting Calendar

Activity When Date Range
Transplant Outdoors January 5 Jan 5 – Jan 19
Direct Sow December 8 Dec 8 – Dec 29
Bloom February 9 Feb 9 – May 11
Fall Sowing September 23 Sep 23 – Oct 7

· 6" apart · Rows 8" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

45–60 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9b

📆 Growing Season

296 days in Putnam County

Growing Tips for Sweet Alyssum in Putnam County

Direct sow Sweet Alyssum outdoors after February 09 in Putnam County when soil has warmed and frost danger has passed.

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

Your generous 297.0-day season in Putnam County allows multiple plantings of Sweet Alyssum. Sow every 22.0 days for continuous harvest.

Common pests for Sweet Alyssum in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Surface-sow seeds — they need light to germinate. Direct-sow as soon as soil can be worked in spring; in zones 7+ also sow in fall. Thin to 6 inches apart. Shear back hard in midsummer when heat causes dormancy — plants recover and re-bloom when cool weather returns. Self-seeds prolifically; allow a few plants to set seed for a perpetual colony.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sweet Alyssum in Putnam County, FL?

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

What planting zone is Putnam County, FL?

Putnam County, Florida is in USDA Hardiness Zone 9b. The average last spring frost is February 9 and first fall frost is December 2.

When should I plant Sweet Alyssum in Putnam County County, ?

In Putnam County County, , plant Sweet Alyssum after the last frost (around February 9) and before the first frost (around December 2). Best results when soil holds above 50°F.

What growing zone is Putnam County County, for Sweet Alyssum?

Putnam County County sits in USDA Zone 9b. Sweet Alyssum grows reliably in zones 3a through 11b, so it's a good fit here.

Can Sweet Alyssum grow in Putnam County County's climate?

Yes — Sweet Alyssum grows well in Putnam County County's temperate climate. Putnam County County averages a 297-day frost-free season, with last frost around February 9 and first frost around December 2.

🌱

Your Putnam County Garden Planner — Free

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

Sources & credits

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