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When to Plant Amaranth in Jefferson County, FL

Amaranth is an ancient grain crop with edible leaves and seeds, rich in protein and micronutrients. It thrives in warm conditions and is drought-tolerant once established.

Jefferson County, Florida is in USDA Zone 8b. The average last spring frost is March 9 and the first fall frost is November 21, giving you a growing season of approximately 257 days.

At an elevation of 105 feet, Jefferson County receives approximately 56 inches of rainfall annually with predominantly sand soil. Summer highs average 95ยฐF, so Amaranth may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Amaranth will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Amaranth root diseases.

Jefferson County, FL (Zone 8b) Long season
257 days
Last Spring Frost March 9
257 growing days
First Fall Frost November 21

Jefferson County Soil Profile

Soil Type

Sand

Soil pH

5.2-5.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (98 days to spare)
Start indoors: Jan 14 Transplant: Mar 18 🍅 Harvest: Jun 17 – Aug 5
Recommended (50%) ✓ Fits season (103 days to spare)
Start indoors: Jan 19 Transplant: Mar 23 🍅 Harvest: Jun 22 – Aug 10
Safe Start (90%) ✓ Fits season (106 days to spare)
Start indoors: Feb 6 Transplant: Apr 10 🍅 Harvest: Jul 10 – Aug 28

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 Jefferson County

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

Soil pH

Your soil pH (5.2โ€“5.9) is more acidic than Amaranth prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Amaranth.

Organic Matter

Organic matter is low (1.3%). Add 2-3 inches of compost before planting Amaranth.

How to Plant Amaranth

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 880 gal / 100 sq ft

Monthly Watering Guide for Amaranth

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

Month Amaranth Needs Rainfall You Supplement Action
Jan โ€” 3" 0" โ„๏ธ Dormant
Feb โ€” 2.9" 0" โ„๏ธ Dormant
Mar 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Apr 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
May 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
Jun 4.3" 7.8" 0" โœ… Rainfall sufficient
Jul 4.3" 8.9" 0" โœ… Rainfall sufficient
Aug 4.3" 7.4" 0" โœ… Rainfall sufficient
Sep 4.3" 6.4" 0" โœ… Rainfall sufficient
Oct 4.3" 5" 0" โœ… Rainfall sufficient
Nov 4.3" 2.5" 1.8" ๐Ÿ’ง Light watering
Dec โ€” 2.7" 0" โ„๏ธ Dormant

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

Amaranth 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.

Amaranth needs ~2,231 GDD — county provides 5,461 GDD Excellent fit

Amaranth Planting Timeline โ€” Jefferson County, FL

Amaranth Planting Calendar

Activity When Date Range
Start Indoors January 19 Jan 19 โ€“ Feb 2
Transplant Outdoors March 23 Mar 23 โ€“ Apr 6
Direct Sow March 16 Mar 16 โ€“ Apr 6
Harvest June 22 Jun 22 โ€“ Aug 10

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Start Indoors
March Transplant Outdoors Direct Sow
April Transplant Outdoors Direct Sow
May โ€”
June Harvest
July Harvest
August Harvest
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

90โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

257 days in Jefferson County

Growing Tips for Amaranth in Jefferson County

Direct sow Amaranth outdoors after March 09 in Jefferson County when soil has warmed and frost danger has passed.

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

General growing tips

Direct sow after last frost when soil is warm. Thin seedlings to 18 inches apart. Harvest leaves when young and tender; harvest seeds when flower heads begin to dry.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Amaranth in Jefferson County, FL?

Jefferson County is in Zone 8b with an average last frost of March 9. Plan your Amaranth planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Jefferson County, FL?

Jefferson County, Florida is in USDA Hardiness Zone 8b. The average last spring frost is March 9 and first fall frost is November 21.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Jefferson County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.

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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 Jefferson County, FL. Local conditions may vary. Last updated: April 2026.