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When to Plant Catnip in Washington County, UT

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.

Washington County, Utah is in USDA Zone 8a. The average last spring frost is April 6 and the first fall frost is November 1, giving you a growing season of approximately 209 days.

At an elevation of 3,524 feet, Washington County receives approximately 12.7 inches of rainfall annually with predominantly loam soil. Summer highs average 90ยฐF, 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.

Washington County, UT (Zone 8a) Long season
209 days
Last Spring Frost April 6
209 growing days
First Fall Frost November 1

Washington County Soil Profile

Soil Type

Loam

Soil pH

6.7-8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (84 days to spare)
Transplant: Mar 20 🍅 Harvest: May 22 – Jul 24
Recommended (50%) ✓ Fits season (76 days to spare)
Transplant: Apr 13 🍅 Harvest: Jun 15 – Aug 17
Safe Start (90%) ✓ Fits season (45 days to spare)
Transplant: Jun 3 🍅 Harvest: Aug 5 – Oct 7

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 Washington County

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

Soil pH

Your soil pH (6.7โ€“8.0) overlaps with Catnip's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Catnip.

Organic Matter

Organic matter is moderate (2.4%). Annual compost additions will help Catnip.

How to Plant Catnip

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

Succession Planting Catnip

4
successive plantings in your 209-day season

Sow every 6.9 weeks. Last sowing by Aug 13 to harvest before frost.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.3″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 881 gal / 100 sq ft
Drought risk

Water stress score is 10/10 โ€” consider drought-tolerant varieties and mulching

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€” 1" 0" โ„๏ธ Dormant
Feb โ€” 0.6" 0" โ„๏ธ Dormant
Mar โ€” 1.1" 0" โ„๏ธ Dormant
Apr 2.2" 1.2" 1" 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" 1.2" 1" ๐Ÿ’ง Light watering
Aug 2.2" 1.4" 0.8" ๐Ÿ’ง Light watering
Sep 2.2" 0.9" 1.3" ๐Ÿšฟ Regular watering
Oct 2.2" 1.2" 1" ๐Ÿ’ง Light watering
Nov 2.2" 1" 1.2" ๐Ÿšฟ Regular watering
Dec โ€” 0.8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Nov in Washington 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 ~1,225 GDD — county provides 3,657 GDD Excellent fit

Catnip Planting Timeline โ€” Washington County, UT

Catnip Planting Calendar

Activity When Date Range
Transplant Outdoors April 13 Apr 13 โ€“ Apr 27
Harvest June 15 Jun 15 โ€“ Aug 17

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 1-2 times/week

๐Ÿ“… Days to Maturity

60โ€“80 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

209 days in Washington County

Growing Tips for Catnip in Washington County

Direct sow Catnip outdoors after April 06 in Washington County when soil has warmed and frost danger has passed.

Washington County receives only 13" 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 Washington County, UT?

Washington County is in Zone 8a with an average last frost of April 6. Plan your Catnip planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Washington County, UT?

Washington County, Utah is in USDA Hardiness Zone 8a. The average last spring frost is April 6 and first fall frost is November 1.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Washington County gardeners in Zone 8a 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 Washington County, UT. Local conditions may vary. Last updated: April 2026.