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When to Plant Rosemary in Jasper County, MO

Jasper County, Missouri Zone 7a May

May to-do list for Jasper County, Missouri

Your garden in Jasper County, Missouri is working on a schedule, even when you're not. Here's where you should be this May.

Avg. last frost April 9
Avg. first frost October 26
Soil temp (4") 63°F
Watering Moderate
Pest pressure Low
Daylight 14 hrs

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Rosemary is an aromatic evergreen shrub with needle-like leaves and a piney, citrus flavor. It is a Mediterranean herb that thrives in warm, dry conditions.

Jasper County, Missouri is in USDA Zone 7a. The average last spring frost is April 9 and the first fall frost is October 26, giving you a growing season of approximately 200 days.

At an elevation of 1,156 feet, Jasper County receives approximately 30.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Rosemary during the growing season.

Jasper County, MO (Zone 7a) Long season
200 days
Last Spring Frost April 9
200 growing days
First Fall Frost October 26

Jasper County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Apr 10 🍅 Harvest: Jul 3 – Nov 20
Recommended (50%) ✗ May not fit
Transplant: Apr 16 🍅 Harvest: Jul 9 – Nov 26
Safe Start (90%) ✗ May not fit
Transplant: Apr 28 🍅 Harvest: Jul 21 – Dec 8

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 Jasper County

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

Soil pH

Your soil pH (5.5–6.6) overlaps with Rosemary's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.8%). Annual compost additions will help Rosemary.

How to Plant Rosemary

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

Succession Planting Rosemary

2
successive plantings in your 200-day season

Sow every 9.1 weeks. Last sowing by Apr 29 to harvest before frost.

Plant Water Budget

Plant needs
0.3″/week
Rainfall provides
0.7″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Rosemary

Rosemary needs approximately 0.3 inches of water per week (1.3" per month). Here's how your county's rainfall compares month by month.

Month Rosemary Needs Rainfall You Supplement Action
Jan 1.3" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 1.8" 0" ❄️ Dormant
Apr 1.3" 2.9" 0" ✅ Rainfall sufficient
May 1.3" 3.5" 0" ✅ Rainfall sufficient
Jun 1.3" 4.3" 0" ✅ Rainfall sufficient
Jul 1.3" 3.1" 0" ✅ Rainfall sufficient
Aug 1.3" 3.6" 0" ✅ Rainfall sufficient
Sep 1.3" 2.5" 0" ✅ Rainfall sufficient
Oct 1.3" 2.4" 0" ✅ Rainfall sufficient
Nov 2.2" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

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

Rosemary 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.

Rosemary needs ~1,885 GDD — county provides 2,900 GDD Excellent fit

Rosemary Planting Timeline — Jasper County, MO

Rosemary Planting Calendar

Activity When Date Range
Transplant Outdoors April 16 Apr 16 – Apr 30
Harvest July 9 Jul 9 – Nov 26

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.3"/week · Natural rainfall sufficient

📅 Days to Maturity

80–180 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

200 days in Jasper County

Growing Tips for Rosemary in Jasper County

Direct sow Rosemary outdoors after April 09 in Jasper County when soil has warmed and frost danger has passed.

General growing tips

Grow in well-drained soil and avoid overwatering. In cold climates, grow in containers and bring indoors for winter. Propagate from stem cuttings for faster results than seed.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Rosemary in Jasper County, MO?

Jasper County is in Zone 7a with an average last frost of April 9. Plan your Rosemary planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jasper County, MO?

Jasper County, Missouri is in USDA Hardiness Zone 7a. The average last spring frost is April 9 and first fall frost is October 26.

🌱

Your Jasper County Garden Planner — Free

A 24-page printable planner built for Jasper 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 Jasper County, MO. 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.