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When to Plant Catnip in Grant County, WA

Catnip is a hardy perennial herb in the mint family known for its effect on cats. It also makes a calming tea and is a useful companion plant that repels some pests.

Grant County, Washington is in USDA Zone 7a. The average last spring frost is April 29 and the first fall frost is October 10, giving you a growing season of approximately 164 days.

At an elevation of 3,122 feet, Grant County receives approximately 17.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Catnip during the growing season. With low rainfall, drip irrigation is essential for growing Catnip successfully. Mulch heavily to conserve soil moisture.

Grant County, WA (Zone 7a) Moderate season
164 days
Last Spring Frost April 29
164 growing days
First Fall Frost October 10

Grant County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.8

Drainage

Well Drained

Monthly Watering Guide for Catnip

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

Month Catnip Needs Rainfall You Supplement Action
Jan 2.7" 0" ❄️ Dormant
Feb 1.8" 0" ❄️ Dormant
Mar 2" 0" ❄️ Dormant
Apr 4.3" 1.5" 2.8" 🚿 Regular watering
May 4.3" 1.1" 3.2" 🚿 Regular watering
Jun 4.3" 0.7" 3.6" 🚿 Regular watering
Jul 4.3" 0.2" 4.1" 🚿 Regular watering
Aug 4.3" 0.4" 3.9" 🚿 Regular watering
Sep 4.3" 0.6" 3.7" 🚿 Regular watering
Oct 4.3" 1.7" 2.6" 🚿 Regular watering
Nov 2.5" 0" ❄️ Dormant
Dec 2.5" 0" ❄️ Dormant

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

Catnip Planting Timeline — Grant County, WA

Catnip Planting Calendar

Activity When Date Range
Transplant Outdoors May 6 May 6 – May 20
Harvest July 8 Jul 8 – Sep 9

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 7a

📆 Growing Season

164 days in Grant County

Growing Tips for Grant County

Direct sow or start indoors. Catnip is very easy to grow and can become invasive. Harvest leaves before flowering for tea. Protect young plants from cats.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Catnip in Grant County, WA?

Grant County is in Zone 7a with an average last frost of April 29. Plan your Catnip planting based on this frost date — see the calendar above for exact timing.

What planting zone is Grant County, WA?

Grant County, Washington is in USDA Hardiness Zone 7a. The average last spring frost is April 29 and first fall frost is October 10.

🌱

Your Grant County Garden Planner — Free

A 22-page printable planner built for Grant County (Zone 7a). 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 Grant County, WA. Local conditions may vary. Last updated: June 2026.

Sources & credits

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