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When to Plant Amaranth in Tillamook County, OR

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.

Tillamook County, Oregon is in USDA Zone 9a. The average last spring frost is April 19 and the first fall frost is October 29, giving you a growing season of approximately 193 days.

At an elevation of 332 feet, Tillamook County receives approximately 40.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Amaranth during the growing season.

Tillamook County, OR (Zone 9a) Moderate season
193 days
Last Spring Frost April 19
193 growing days
First Fall Frost October 29

Tillamook County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.5

Drainage

Well Drained

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 5.4" 0" ❄️ Dormant
Feb 4.1" 0" ❄️ Dormant
Mar 4.1" 0" ❄️ Dormant
Apr 4.3" 3.4" 0.9" 💧 Light watering
May 4.3" 2.5" 1.8" 💧 Light watering
Jun 4.3" 1.8" 2.5" 🚿 Regular watering
Jul 4.3" 0.7" 3.6" 🚿 Regular watering
Aug 4.3" 0.8" 3.5" 🚿 Regular watering
Sep 4.3" 1.8" 2.5" 🚿 Regular watering
Oct 4.3" 3.7" 0.6" 💧 Light watering
Nov 6.4" 0" ❄️ Dormant
Dec 6.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Tillamook County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Amaranth Planting Timeline — Tillamook County, OR

Amaranth Planting Calendar

Activity When Date Range
Start Indoors March 8 Mar 8 – Mar 22
Transplant Outdoors April 26 Apr 26 – May 10
Direct Sow April 19 Apr 19 – May 10
Harvest July 26 Jul 26 – Sep 13

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
June
July Harvest
August Harvest
September Harvest
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

90–120 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 9a

📆 Growing Season

193 days in Tillamook County

Growing Tips for Tillamook County

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 Tillamook County, OR?

Tillamook County is in Zone 9a with an average last frost of April 19. Plan your Amaranth planting based on this frost date — see the calendar above for exact timing.

What planting zone is Tillamook County, OR?

Tillamook County, Oregon is in USDA Hardiness Zone 9a. The average last spring frost is April 19 and first fall frost is October 29.

🌱

Your Tillamook County Garden Planner — Free

A 22-page printable planner built for Tillamook County (Zone 9a). 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 Tillamook County, OR. Local conditions may vary. Last updated: July 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.