Blog

When to Plant Chamomile in Humboldt County, CA

Humboldt County, California Zone 9b May

May to-do list for Humboldt County, California

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

Avg. last frost February 27
Avg. first frost November 28
Soil temp (4") 74°F
Watering Critical
Pest pressure High
Daylight 14.3 hrs
  1. Basket week: chamomile

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

A few tasks this May that'll pay off in June
  • First harvests: chamomile

Instant PDF download. No spam, unsubscribe any time.

Chamomile is a daisy-like herb famous for its calming, apple-scented tea. German chamomile is an annual while Roman chamomile is a perennial ground cover.

Humboldt County, California is in USDA Zone 9b. The average last spring frost is February 27 and the first fall frost is November 28, giving you a growing season of approximately 274 days.

At an elevation of 148 feet, Humboldt County receives approximately 22.1 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 87°F, providing good warmth for Chamomile during the growing season. Sandy soil warms quickly in spring — great for early planting — but Chamomile will need more frequent watering and organic matter to retain nutrients.

Humboldt County, CA (Zone 9b) Year-round
274 days
Last Spring Frost February 27
274 growing days
First Fall Frost November 28

Humboldt County Soil Profile

Soil Type

Sandy Loam

Soil pH

6.2-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (157 days to spare)
Start indoors: Jan 16 Transplant: Feb 6 🍅 Harvest: Apr 10 – Jun 19
Recommended (50%) ✓ Fits season (148 days to spare)
Start indoors: Jan 30 Transplant: Feb 20 🍅 Harvest: Apr 24 – Jul 3
Safe Start (90%) ✓ Fits season (134 days to spare)
Start indoors: Mar 5 Transplant: Mar 26 🍅 Harvest: May 28 – Aug 6

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 Humboldt County

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

Soil pH

Your soil pH (6.2–6.8) is within Chamomile's preferred range (5.6–7.5).

Soil Texture

Sandy soil in Humboldt County warms quickly in spring but drains fast. Chamomile will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Chamomile.

How to Plant Chamomile

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

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Chamomile

5
successive plantings in your 274-day season

Sow every 6.9 weeks. Last sowing by Aug 30 to harvest before frost.

For a dedicated fall crop, sow by Oct 03.

Plant Water Budget

Plant needs
0.4″/week
Rainfall provides
0.3″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 153 gal / 100 sq ft

Monthly Watering Guide for Chamomile

Chamomile needs approximately 0.4 inches of water per week (1.7" per month). Here's how your county's rainfall compares month by month.

Month Chamomile Needs Rainfall You Supplement Action
Jan 4.8" 0" ❄️ Dormant
Feb 1.7" 5" 0" ✅ Rainfall sufficient
Mar 1.7" 3.3" 0" ✅ Rainfall sufficient
Apr 1.7" 1.7" 0" ✅ Rainfall sufficient
May 1.7" 0.5" 1.2" 🚿 Regular watering
Jun 1.7" 0.1" 1.6" 🚿 Regular watering
Jul 1.7" 0" 1.7" 🚿 Regular watering
Aug 1.7" 0" 1.7" 🚿 Regular watering
Sep 1.7" 0.3" 1.4" 🚿 Regular watering
Oct 1.7" 0.8" 0.9" 🚿 Regular watering
Nov 1.7" 1.9" 0" ✅ Rainfall sufficient
Dec 3.7" 0" ❄️ Dormant

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

Chamomile 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.

Chamomile needs ~1,144 GDD — county provides 4,193 GDD Excellent fit

Chamomile Planting Timeline — Humboldt County, CA

Chamomile Planting Calendar

Activity When Date Range
Start Indoors January 30 Jan 30 – Feb 13
Transplant Outdoors February 20 Feb 20 – Mar 6
Direct Sow February 6 Feb 6 – Feb 27
Harvest April 24 Apr 24 – Jul 3
Fall Sowing October 3 Oct 3 – Oct 17

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.4"/week · Only during dry spells

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 5.6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 9b

📆 Growing Season

274 days in Humboldt County

Growing Tips for Chamomile in Humboldt County

Direct sow Chamomile outdoors after February 27 in Humboldt County when soil has warmed and frost danger has passed.

Sandy soil in Humboldt County dries quickly — mulch Chamomile with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Common pests for Chamomile in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow on the soil surface as seeds need light. Harvest flowers when petals begin to curl back. Chamomile self-sows freely and improves the health of nearby plants.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Chamomile in Humboldt County, CA?

Humboldt County is in Zone 9b with an average last frost of February 27. Plan your Chamomile planting based on this frost date — see the calendar above for exact timing.

What planting zone is Humboldt County, CA?

Humboldt County, California is in USDA Hardiness Zone 9b. The average last spring frost is February 27 and first fall frost is November 28.

🌱

Your Humboldt County Garden Planner — Free

A 24-page printable planner built for Humboldt 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 Humboldt 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.