Blog

When to Plant Catnip in Union County, AR

Union County, Arkansas Zone 8b May

May in the garden — Union County, Arkansas

A quick May briefing for Union County, Arkansas gardeners — what's urgent, what's next, and what can wait.

Avg. last frost March 22
Avg. first frost November 3
Soil temp (4") 74°F
Watering Low
Pest pressure High
Daylight 13.7 hrs
  1. Start harvesting catnip

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

June prep starts now
  • First harvests: catnip

Instant PDF download. No spam, unsubscribe any time.

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.

Union County, Arkansas is in USDA Zone 8b. The average last spring frost is March 22 and the first fall frost is November 3, giving you a growing season of approximately 226 days.

At an elevation of 508 feet, Union County receives approximately 52 inches of rainfall annually with predominantly silt loam soil. Summer highs average 92°F, providing good warmth for Catnip during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Catnip root diseases.

Union County, AR (Zone 8b) Long season
226 days
Last Spring Frost March 22
226 growing days
First Fall Frost November 3
Share this guide:

Union County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (97 days to spare)
Transplant: Mar 20 🍅 Harvest: May 22 – Jul 24
Recommended (50%) ✓ Fits season (93 days to spare)
Transplant: Mar 29 🍅 Harvest: May 31 – Aug 2
Safe Start (90%) ✓ Fits season (92 days to spare)
Transplant: Apr 20 🍅 Harvest: Jun 22 – Aug 24

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 Union County

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

Soil pH

Your soil pH (5.8–6.6) overlaps with Catnip's range (6.0–7.5), though not a perfect match.

Soil Texture

The silt loam soil in Union County is excellent for Catnip — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.7%). 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 226-day season

Sow every 6.9 weeks. Last sowing by Aug 15 to harvest before frost.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 4.8" 0" ❄️ Dormant
Feb 4.5" 0" ❄️ Dormant
Mar 2.2" 4.5" 0" ✅ Rainfall sufficient
Apr 2.2" 3.9" 0" ✅ Rainfall sufficient
May 2.2" 4.6" 0" ✅ Rainfall sufficient
Jun 2.2" 4.4" 0" ✅ Rainfall sufficient
Jul 2.2" 5.1" 0" ✅ Rainfall sufficient
Aug 2.2" 5.1" 0" ✅ Rainfall sufficient
Sep 2.2" 4.2" 0" ✅ Rainfall sufficient
Oct 2.2" 3.5" 0" ✅ Rainfall sufficient
Nov 2.2" 3.8" 0" ✅ Rainfall sufficient
Dec 3.6" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Union County). Supplement amounts are based on average rainfall — 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" — 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.

Catnip needs ~1,330 GDD — county provides 4,294 GDD Excellent fit

Catnip Planting Timeline — Union County, AR

Catnip Planting Calendar

Activity When Date Range
Transplant Outdoors March 29 Mar 29 – Apr 12
Harvest May 31 May 31 – Aug 2

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 8b

📆 Growing Season

226 days in Union County

Growing Tips for Catnip in Union County

Direct sow Catnip outdoors after March 22 in Union County when soil has warmed and frost danger has passed.

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 Union County, AR?

Union County is in Zone 8b with an average last frost of March 22. Plan your Catnip planting based on this frost date — see the calendar above for exact timing.

What planting zone is Union County, AR?

Union County, Arkansas is in USDA Hardiness Zone 8b. The average last spring frost is March 22 and first fall frost is November 3.

🌱

Your Union County Garden Planner — Free

A 24-page printable planner built for Union County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

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