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When to Plant Serviceberries in Modoc County, CA

Modoc County, California Zone 6b May

May in the garden — Modoc County, California

Welcome to May in Zone 6b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost May 31
Avg. first frost September 21
Soil temp (4") 57°F
Watering Critical
Pest pressure Low
Daylight 14.3 hrs
Coming up in June — start thinking about
  • Transplants going out: serviceberries

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Serviceberries (saskatoons) are attractive native shrubs or small trees producing sweet, blueberry-like fruits. They have beautiful spring flowers and vibrant fall color.

Modoc County, California is in USDA Zone 6b. The average last spring frost is May 31 and the first fall frost is September 21, giving you a growing season of approximately 113 days.

At an elevation of 2,205 feet, Modoc County receives approximately 28.3 inches of rainfall annually with predominantly loam soil. Summer highs average 83°F, so choose short-season varieties of Serviceberries to ensure they mature before fall.

Modoc County, CA (Zone 6b) Short season
113 days
Last Spring Frost May 31
113 growing days
First Fall Frost September 21
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Modoc County Soil Profile

Soil Type

Loam

Soil pH

5.9-7.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Jun 9
Recommended (50%) ✓ Fits season
Transplant: Jun 21
Safe Start (90%) ✓ Fits season
Transplant: Jul 10

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 Modoc County

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

Soil pH

Your soil pH (5.9–7.4) overlaps with Serviceberries's range (5.5–7.0), though not a perfect match.

Soil Texture

The loam soil in Modoc County is excellent for Serviceberries — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Serviceberries.

Organic Matter

Organic matter is moderate (2.1%). Annual compost additions will help Serviceberries.

How to Plant Serviceberries

120"
Between Plants
144"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 299 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Serviceberries

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

Month Serviceberries Needs Rainfall You Supplement Action
Jan 5.6" 0" ❄️ Dormant
Feb 5.8" 0" ❄️ Dormant
Mar 4.1" 0" ❄️ Dormant
Apr 2.1" 0" ❄️ Dormant
May 4.3" 0.7" 3.6" 🚿 Regular watering
Jun 4.3" 0.1" 4.2" 🚿 Regular watering
Jul 4.3" 0" 4.3" 🚿 Regular watering
Aug 4.3" 0" 4.3" 🚿 Regular watering
Sep 4.3" 0.4" 3.9" 🚿 Regular watering
Oct 1.3" 0" ❄️ Dormant
Nov 2.7" 0" ❄️ Dormant
Dec 5.5" 0" ❄️ Dormant

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

Serviceberries 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.

Serviceberries needs ~11,178 GDD — county provides 1,384 GDD May not mature

Serviceberries Planting Timeline — Modoc County, CA

Serviceberries Planting Calendar

Activity When Date Range
Transplant Outdoors June 21 Jun 21 – Jul 5

· 120" apart · Rows 144" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

730–1095 days

🧪 Soil pH

Needs 5.5–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

113 days in Modoc County

Growing Tips for Serviceberries in Modoc County

Direct sow Serviceberries outdoors after May 31 in Modoc County when soil has warmed and frost danger has passed.

Your 113.0-day growing season in Modoc County is tight for Serviceberries (730.0-1095.0 days to maturity). Start indoors and choose early-maturing varieties.

General growing tips

Plant in well-drained soil. Minimal pruning needed beyond removing dead wood. Protect fruit from birds with netting. Berries ripen in early summer and are excellent fresh or in pies.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Serviceberries in Modoc County, CA?

Modoc County is in Zone 6b with an average last frost of May 31. Plan your Serviceberries planting based on this frost date — see the calendar above for exact timing.

What planting zone is Modoc County, CA?

Modoc County, California is in USDA Hardiness Zone 6b. The average last spring frost is May 31 and first fall frost is September 21.

🌱

Your Modoc County Garden Planner — Free

A 24-page printable planner built for Modoc County (Zone 6b). 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 Modoc 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.