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When to plant Basil in Louisa County, IA

Plant Basil in Louisa County, when soil hits 50°F — usually April 23. Continue planting through May 14 for the spring crop.

When to Plant Basil in Louisa County, IA

Basil

Basil is a fragrant warm-season herb essential to Italian and Thai cuisines. It comes in many varieties including sweet, Thai, purple, and lemon types.

Louisa County, Iowa is in USDA Zone 5b. The average last spring frost is April 16 and the first fall frost is October 16, giving you a growing season of approximately 183 days.

At an elevation of 1,022 feet, Louisa County receives approximately 38.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Basil during the growing season.

Louisa County, IA (Zone 5b) Moderate season
183 days
Last Spring Frost April 16
183 growing days
First Fall Frost October 16

Louisa County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7.3

Drainage

Well Drained

Monthly Watering Guide for Basil

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

Month Basil Needs Rainfall You Supplement Action
Jan 1.7" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 4.3" 4.2" 0.1" 💧 Light watering
May 4.3" 4.5" 0" ✅ Rainfall sufficient
Jun 4.3" 5.2" 0" ✅ Rainfall sufficient
Jul 4.3" 4.1" 0.2" 💧 Light watering
Aug 4.3" 4" 0.3" 💧 Light watering
Sep 4.3" 3.4" 0.9" 💧 Light watering
Oct 4.3" 2.7" 1.6" 💧 Light watering
Nov 2.5" 0" ❄️ Dormant
Dec 2.4" 0" ❄️ Dormant

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

Basil Planting Timeline — Louisa County, IA

Basil Planting Calendar

Activity When Date Range
Start Indoors February 26 Feb 26 – Mar 12
Transplant Outdoors April 30 Apr 30 – May 14
Direct Sow April 23 Apr 23 – May 14
Harvest June 25 Jun 25 – Aug 27

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

50–75 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5b

📆 Growing Season

183 days in Louisa County

Growing Tips for Louisa County

Start seeds indoors or direct sow after last frost. Pinch flower buds to extend leaf production. Harvest leaves from the top down, cutting just above a leaf pair.

Companion Planting

Good Companions

Avoid Planting Near

  • Rue
  • Sage

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Basil Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Let flower spikes dry brown on the plant.
Storage Store airtight; viable 5 years at 35°F, under 45% humidity.

Isolate 150 ft between varieties. Different basil species can cross.

Frequently Asked Questions

When should I plant Basil in Louisa County, IA?

Louisa County is in Zone 5b with an average last frost of April 16. Plan your Basil planting based on this frost date — see the calendar above for exact timing.

What planting zone is Louisa County, IA?

Louisa County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 16 and first fall frost is October 16.

When should I plant Basil in Louisa County, IA?

In Louisa County, IA, plant Basil after the last frost (around April 16) and before the first frost (around October 16). Best results when soil holds above 50°F.

What growing zone is Louisa County, IA for Basil?

Louisa County sits in USDA Zone 5b. Basil grows reliably in zones 4a through 11b, so it's a good fit here.

Can Basil grow in Louisa County's climate?

Yes — Basil grows well in Louisa County's temperate climate. Louisa County averages a 183-day frost-free season, with last frost around April 16 and first frost around October 16.

🌱

Your Louisa County Garden Planner — Free

A 22-page printable planner built for Louisa County (Zone 5b). 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 Louisa County, IA. 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.