When to Plant Amaranth in Duval County, FL
Your May gardening checklist
Welcome to May in Zone 9b. These are the moves that will have the biggest impact on your growing season.
Get ahead of June
- First harvests: amaranth
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.
Duval County, Florida is in USDA Zone 9b. The average last spring frost is February 24 and the first fall frost is November 29, giving you a growing season of approximately 278 days.
At an elevation of 337 feet, Duval County receives approximately 56.9 inches of rainfall annually with predominantly sand soil. Summer highs average 102°F, so Amaranth may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — 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.
Duval County Soil Profile
Soil Type
Sand
Soil pH
5-5.8
Drainage
Well Drained
Plant Planting Risk Windows
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 Duval County
How your county's soil matches Amaranth's growing requirements.
Soil pH
Your soil pH (5.0–5.8) is more acidic than Amaranth prefers (6.0–7.5). Add garden lime to raise pH.
Soil Texture
Sandy soil in Duval County warms quickly in spring but drains fast. Amaranth will need more frequent watering and regular compost additions to retain nutrients.
Organic Matter
Organic matter is low (1.4%). Add 2-3 inches of compost before planting Amaranth.
How to Plant Amaranth
Plant Water Budget
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 | — | 2.6" | 0" | ❄️ Dormant |
| Feb | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Mar | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Apr | 4.3" | 3" | 1.3" | 💧 Light watering |
| May | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Jun | 4.3" | 8.7" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 7.8" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 8.9" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 6.3" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Nov | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| Dec | — | 2.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Feb–Nov in Duval County). Supplement amounts are based on average rainfall — 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" — 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.
Amaranth Planting Timeline — Duval County, FL
Amaranth Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 13 | Jan 13 – Jan 27 |
| Transplant Outdoors | March 3 | Mar 3 – Mar 17 |
| Direct Sow | February 24 | Feb 24 – Mar 17 |
| Harvest | June 2 | Jun 2 – Jul 21 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | — |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–7.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 9b
📆 Growing Season
278 days in Duval County
Growing Tips for Amaranth in Duval County
Direct sow Amaranth outdoors after February 24 in Duval County when soil has warmed and frost danger has passed.
Sandy soil in Duval County dries quickly — mulch Amaranth with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
With summer highs reaching 102°F in Duval County, provide afternoon shade for Amaranth and water deeply in the morning.
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
Check more plant combinations with our Companion Planting Checker →
Amaranth in Other Locations
Frequently Asked Questions
When should I plant Amaranth in Duval County, FL?
Duval County is in Zone 9b with an average last frost of February 24. Plan your Amaranth planting based on this frost date — see the calendar above for exact timing.
What planting zone is Duval County, FL?
Duval County, Florida is in USDA Hardiness Zone 9b. The average last spring frost is February 24 and first fall frost is November 29.
Your Duval County Garden Planner — Free
A 24-page printable planner built for Duval 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.