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When to Plant Catnip in Benton 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.

Benton County, Washington is in USDA Zone 7a. The average last spring frost is April 3 and the first fall frost is October 27, giving you a growing season of approximately 207 days.

At an elevation of 2,633 feet, Benton County receives approximately 22.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Catnip during the growing season.

Benton County, WA (Zone 7a) Long season
207 days
Last Spring Frost April 3
207 growing days
First Fall Frost October 27

Benton County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (79 days to spare)
Transplant: Mar 31 🍅 Harvest: Jun 2 – Aug 4
Recommended (50%) ✓ Fits season (74 days to spare)
Transplant: Apr 10 🍅 Harvest: Jun 12 – Aug 14
Safe Start (90%) ✓ Fits season (71 days to spare)
Transplant: Apr 27 🍅 Harvest: Jun 29 – Aug 31

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 Benton County

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

Soil pH

Your soil pH (5.5โ€“6.3) is more acidic than Catnip prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Benton County is excellent for Catnip โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.6%) โ€” Catnip will thrive.

How to Plant Catnip

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Catnip

4
successive plantings in your 207-day season

Sow every 6.9 weeks. Last sowing by Aug 08 to harvest before frost.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.5″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 80 gal / 100 sq ft

Monthly Watering Guide for Catnip

Catnip needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Catnip Needs Rainfall You Supplement Action
Jan โ€” 3.2" 0" โ„๏ธ Dormant
Feb โ€” 2.6" 0" โ„๏ธ Dormant
Mar โ€” 2.1" 0" โ„๏ธ Dormant
Apr 2.2" 1.5" 0.7" ๐Ÿ’ง Light watering
May 2.2" 1.4" 0.8" ๐Ÿ’ง Light watering
Jun 2.2" 0.9" 1.3" ๐Ÿšฟ Regular watering
Jul 2.2" 0.4" 1.8" ๐Ÿšฟ Regular watering
Aug 2.2" 0.4" 1.8" ๐Ÿšฟ Regular watering
Sep 2.2" 0.8" 1.4" ๐Ÿšฟ Regular watering
Oct 2.2" 2" 0.2" ๐Ÿ’ง Light watering
Nov โ€” 3.7" 0" โ„๏ธ Dormant
Dec โ€” 3.5" 0" โ„๏ธ Dormant

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

Catnip 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.

Catnip needs ~1,120 GDD — county provides 3,312 GDD Excellent fit

Catnip Planting Timeline โ€” Benton County, WA

Catnip Planting Calendar

Activity When Date Range
Transplant Outdoors April 10 Apr 10 โ€“ Apr 24
Harvest June 12 Jun 12 โ€“ Aug 14

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Transplant Outdoors
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

0.5"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

60โ€“80 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

207 days in Benton County

Growing Tips for Catnip in Benton County

Direct sow Catnip outdoors after April 03 in Benton County when soil has warmed and frost danger has passed.

Benton County receives only 22" of rain annually. Catnip needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

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 Benton County, WA?

Benton County is in Zone 7a with an average last frost of April 3. Plan your Catnip planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Benton County, WA?

Benton County, Washington is in USDA Hardiness Zone 7a. The average last spring frost is April 3 and first fall frost is October 27.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Benton County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Benton County, WA. Local conditions may vary. Last updated: April 2026.