When to Plant Amaranth in Story County, IA
May in Story County, Iowa — your action list
Your garden in Story County, Iowa is working on a schedule, even when you're not. Here's where you should be this May.
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Move amaranth from tray to bed
Water the tray well an hour before you transplant. Roots slide out cleanly and settle in faster.
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Outdoor sowing time: amaranth
Rake a smooth bed, make a shallow furrow, drop seeds at the spacing on the packet, water gently, walk away.
Before June arrives, get these ready
- Starting indoors: 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.
Story County, Iowa is in USDA Zone 5b. The average last spring frost is April 30 and the first fall frost is October 7, giving you a growing season of approximately 160 days.
At an elevation of 1,177 feet, Story County receives approximately 34.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Amaranth to ensure they mature before fall.
Story County Soil Profile
Soil Type
Silt Loam
Soil pH
6-6.8
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 Story County
How your county's soil matches Amaranth's growing requirements.
Soil pH
Your soil pH (6.0–6.8) is within Amaranth's preferred range (6.0–7.5).
Soil Texture
The silt loam soil in Story County is excellent for Amaranth — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.2%) — Amaranth will thrive.
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 | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.3" | 1" | 💧 Light watering |
| May | 4.3" | 4" | 0.3" | 💧 Light watering |
| Jun | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Aug | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Sep | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Oct | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Nov | — | 2.2" | 0" | ❄️ Dormant |
| Dec | — | 1.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Story 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 — Story County, IA
Amaranth Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 5 | Mar 5 – Mar 19 |
| Transplant Outdoors | May 14 | May 14 – May 28 |
| Direct Sow | May 7 | May 7 – May 28 |
| Harvest | August 13 | Aug 13 – Oct 1 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| 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: ideal
🗺️ USDA Zone
Zone 5b
📆 Growing Season
160 days in Story County
Growing Tips for Amaranth in Story County
Direct sow Amaranth outdoors after April 30 in Story County when soil has warmed and frost danger has passed.
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 Story County, IA?
Story County is in Zone 5b with an average last frost of April 30. Plan your Amaranth planting based on this frost date — see the calendar above for exact timing.
What planting zone is Story County, IA?
Story County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 30 and first fall frost is October 7.
Your Story County Garden Planner — Free
A 24-page printable planner built for Story County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.