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When to Plant Crosne in Putnam County, FL

Putnam County, Florida Zone 9b May

Top priorities for Putnam County, Florida gardeners in May

We've pulled the most time-sensitive tasks for Putnam County, Florida this May and put them front and centre. Tackle them in order.

Avg. last frost February 9
Avg. first frost December 2
Soil temp (4") 76°F
Watering Moderate
Pest pressure High
Daylight 13.5 hrs
To set up a strong June, finish these tasks
  • First harvests: crosne

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Crosne (Chinese artichoke) produces small, segmented white tubers with a crunchy texture and mild artichoke-nutty flavor. They are a rare delicacy in French cuisine.

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 Crosne may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Crosne will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Crosne root diseases.

Putnam County, FL (Zone 9b) Year-round
296 days
Last Spring Frost February 9
296 growing days
First Fall Frost December 2
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Putnam County Soil Profile

Soil Type

Sand

Soil pH

4.9-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (87 days to spare)
Transplant: Jan 25 🍅 Harvest: Jun 28 – Aug 30
Recommended (50%) ✓ Fits season (79 days to spare)
Transplant: Feb 9 🍅 Harvest: Jul 13 – Sep 14
Safe Start (90%) ✓ Fits season (80 days to spare)
Transplant: Mar 4 🍅 Harvest: Aug 5 – Oct 7

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 Crosne's growing requirements.

Soil pH

Your soil pH (4.9–6.2) is more acidic than Crosne prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Crosne.

Organic Matter

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

How to Plant Crosne

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 1,544 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Crosne

Crosne needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Crosne Needs Rainfall You Supplement Action
Jan 2.4" 0" ❄️ Dormant
Feb 4.3" 2.6" 1.7" 💧 Light watering
Mar 4.3" 3.5" 0.8" 💧 Light watering
Apr 4.3" 2.3" 2" 💧 Light watering
May 4.3" 3.3" 1" 💧 Light watering
Jun 4.3" 7.9" 0" ✅ Rainfall sufficient
Jul 4.3" 9.4" 0" ✅ Rainfall sufficient
Aug 4.3" 8.7" 0" ✅ Rainfall sufficient
Sep 4.3" 7.4" 0" ✅ Rainfall sufficient
Oct 4.3" 5.3" 0" ✅ Rainfall sufficient
Nov 4.3" 2.2" 2.1" 💧 Light watering
Dec 4.3" 2.6" 1.7" 💧 Light watering

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.

Crosne 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.

Crosne needs ~3,719 GDD — county provides 6,311 GDD Excellent fit

Crosne Planting Timeline — Putnam County, FL

Crosne Planting Calendar

Activity When Date Range
Direct Sow January 19 Jan 19 – Feb 9
Harvest June 22 Jun 22 – Aug 24
Fall Sowing October 7 Oct 7 – Oct 21

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January Direct Sow
February Direct Sow
March
April
May
June Harvest
July Harvest
August Harvest
September
October Fall Sowing
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

150–200 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9b

📆 Growing Season

296 days in Putnam County

Growing Tips for Crosne in Putnam County

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

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

General growing tips

Plant tubers 3 inches deep in spring. Mark the location well as plants die back. Harvest in late fall after frost. Leave some tubers in ground for next year. Very labor-intensive to harvest.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Crosne in Putnam County, FL?

Putnam County is in Zone 9b with an average last frost of February 9. Plan your Crosne 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.

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Your Putnam County Garden Planner — Free

A 24-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: May 2026.

Sources & credits

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