Blog

When to Plant Lemon Balm in Tehama County, CA

Tehama County, California Zone 9b May

May in the garden — Tehama County, California

Your Tehama County, California garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.

Avg. last frost March 6
Avg. first frost November 28
Soil temp (4") 72°F
Watering High
Pest pressure High
Daylight 14.2 hrs
  1. Basket week: lemon balm

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

Get ahead of June
  • First harvests: lemon balm

Instant PDF download. No spam, unsubscribe any time.

Lemon balm is a vigorous perennial herb with bright green, lemon-scented leaves. It makes a refreshing tea and is easy to grow but can spread aggressively.

Tehama County, California is in USDA Zone 9b. The average last spring frost is March 6 and the first fall frost is November 28, giving you a growing season of approximately 267 days.

At an elevation of 78 feet, Tehama County receives approximately 44 inches of rainfall annually with predominantly loam soil. Summer highs average 82°F, so choose short-season varieties of Lemon Balm to ensure they mature before fall.

Tehama County, CA (Zone 9b) Long season
267 days
Last Spring Frost March 6
267 growing days
First Fall Frost November 28

Tehama County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (151 days to spare)
Transplant: Mar 2 🍅 Harvest: May 4 – Jun 22
Recommended (50%) ✓ Fits season (148 days to spare)
Transplant: Mar 13 🍅 Harvest: May 15 – Jul 3
Safe Start (90%) ✓ Fits season (126 days to spare)
Transplant: Apr 25 🍅 Harvest: Jun 27 – Aug 15

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 Tehama County

How your county's soil matches Lemon Balm's growing requirements.

Soil pH

Your soil pH (6.8–7.6) overlaps with Lemon Balm's range (5.5–7.5), though not a perfect match.

Soil Texture

The loam soil in Tehama County is excellent for Lemon Balm — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.9%). Annual compost additions will help Lemon Balm.

How to Plant Lemon Balm

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

Succession Planting Lemon Balm

5
successive plantings in your 267-day season

Sow every 6.9 weeks. Last sowing by Sep 19 to harvest before frost.

Plant Water Budget

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

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Lemon Balm

Lemon Balm 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 Lemon Balm Needs Rainfall You Supplement Action
Jan 10.2" 0" ❄️ Dormant
Feb 8.5" 0" ❄️ Dormant
Mar 2.2" 7" 0" ✅ Rainfall sufficient
Apr 2.2" 3.5" 0" ✅ Rainfall sufficient
May 2.2" 1.3" 0.9" 💧 Light watering
Jun 2.2" 0.2" 2" 🚿 Regular watering
Jul 2.2" 0" 2.2" 🚿 Regular watering
Aug 2.2" 0" 2.2" 🚿 Regular watering
Sep 2.2" 0.4" 1.8" 🚿 Regular watering
Oct 2.2" 1.8" 0.4" 💧 Light watering
Nov 2.2" 4.2" 0" ✅ Rainfall sufficient
Dec 6.9" 0" ❄️ Dormant

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

Lemon Balm 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.

Lemon Balm needs ~748 GDD — county provides 3,070 GDD Excellent fit

Lemon Balm Planting Timeline — Tehama County, CA

Lemon Balm Planting Calendar

Activity When Date Range
Transplant Outdoors March 13 Mar 13 – Mar 27
Harvest May 15 May 15 – Jul 3

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

60–70 days

🧪 Soil pH

Needs 5.5–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 9b

📆 Growing Season

267 days in Tehama County

Growing Tips for Lemon Balm in Tehama County

Direct sow Lemon Balm outdoors after March 06 in Tehama County when soil has warmed and frost danger has passed.

General growing tips

Start from seed, cuttings, or divisions. Contain in pots or use barriers to prevent spreading. Harvest frequently to keep plants bushy and prevent flowering.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Lemon Balm in Tehama County, CA?

Tehama County is in Zone 9b with an average last frost of March 6. Plan your Lemon Balm planting based on this frost date — see the calendar above for exact timing.

What planting zone is Tehama County, CA?

Tehama County, California is in USDA Hardiness Zone 9b. The average last spring frost is March 6 and first fall frost is November 28.

🌱

Your Tehama County Garden Planner — Free

A 24-page printable planner built for Tehama County (Zone 9b). 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 Tehama County, CA. 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.