Blog

When to Plant Sunchoke in Pinellas County, FL

Sunchokes (Jerusalem artichokes) are a native sunflower relative grown for their knobby, nutty-flavored tubers. They are extremely productive and nearly impossible to eradicate.

Pinellas County, Florida is in USDA Zone 9b. The average last spring frost is January 25 and the first fall frost is December 16, giving you a growing season of approximately 325 days.

At an elevation of 246 feet, Pinellas County receives approximately 58.1 inches of rainfall annually with predominantly sand soil. Summer highs average 102ยฐF, so Sunchoke may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Sunchoke will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sunchoke root diseases.

Pinellas County, FL (Zone 9b) Year-round
325 days
Last Spring Frost January 25
325 growing days
First Fall Frost December 16

Pinellas County Soil Profile

Soil Type

Sand

Soil pH

5.1-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (143 days to spare)
Transplant: Feb 2 🍅 Harvest: May 25 – Jul 20
Recommended (50%) ✓ Fits season (143 days to spare)
Transplant: Feb 8 🍅 Harvest: May 31 – Jul 26
Safe Start (90%) ✓ Fits season (117 days to spare)
Transplant: Mar 14 🍅 Harvest: Jul 4 – Aug 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 Pinellas County

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

Soil pH

Your soil pH (5.1โ€“6.2) is more acidic than Sunchoke prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Sunchoke.

Organic Matter

Organic matter is low (1.5%). Add 2-3 inches of compost before planting Sunchoke.

How to Plant Sunchoke

1"
Planting Depth
30"
Between Plants
42"
Between Rows

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 1,600 gal / 100 sq ft

Monthly Watering Guide for Sunchoke

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

Month Sunchoke Needs Rainfall You Supplement Action
Jan 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
Feb 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Mar 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Apr 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
May 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Jun 4.3" 7.6" 0" โœ… Rainfall sufficient
Jul 4.3" 8.5" 0" โœ… Rainfall sufficient
Aug 4.3" 8.7" 0" โœ… Rainfall sufficient
Sep 4.3" 7.1" 0" โœ… Rainfall sufficient
Oct 4.3" 5.3" 0" โœ… Rainfall sufficient
Nov 4.3" 2.5" 1.8" ๐Ÿ’ง Light watering
Dec 4.3" 2.6" 1.7" ๐Ÿ’ง Light watering

Water needs are for active growing months only (Janโ€“Dec in Pinellas County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Sunchoke 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" โ€” every day above 50ยฐF 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.

Sunchoke needs ~3,445 GDD — county provides 8,639 GDD Excellent fit

Sunchoke Planting Timeline โ€” Pinellas County, FL

Sunchoke Planting Calendar

Activity When Date Range
Transplant Outdoors February 8 Feb 8 โ€“ Feb 22
Harvest May 31 May 31 โ€“ Jul 26

Plant 1" deep ยท 30" apart ยท Rows 42" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

110โ€“150 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 9b

๐Ÿ“† Growing Season

325 days in Pinellas County

Growing Tips for Sunchoke in Pinellas County

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

Sandy soil in Pinellas County dries quickly โ€” mulch Sunchoke with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 102ยฐF in Pinellas County, provide afternoon shade for Sunchoke and water deeply in the morning.

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

General growing tips

Plant tubers 4 inches deep in early spring. Contain plants with barriers as they spread aggressively. Harvest after frost or leave in ground and dig as needed through winter.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sunchoke in Pinellas County, FL?

Pinellas County is in Zone 9b with an average last frost of January 25. Plan your Sunchoke planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Pinellas County, FL?

Pinellas County, Florida is in USDA Hardiness Zone 9b. The average last spring frost is January 25 and first fall frost is December 16.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Pinellas County gardeners in Zone 9b 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 Pinellas County, FL. Local conditions may vary. Last updated: April 2026.