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When to plant Crocus in Modoc County County,

The best window to plant Crocus in Modoc County County, is mid-spring–late spring, when soil warms to 50°F. Last frost typically hits May 31; first frost September 21. A second sowing from August 10 to August 24 extends the harvest into fall.

When to Plant Crocus in Modoc County, CA

Modoc County, California Zone 6b June

June to-do list for Modoc County, California

Welcome to June 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") 68°F
Watering Critical
Pest pressure High
Daylight 15 hrs

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Crocuses (Crocus spp.) are the heralds of spring — small, gem-like blooms that push up through frozen ground or even snow, often weeks before any other flower. Their compact corms naturalize readily in lawns, rock gardens, and borders, creating drifts of purple, white, and yellow that expand year after year. Bees prize early crocus as one of their first nectar and pollen sources of the season. The saffron crocus (C. sativus) blooms in fall and yields the world's most expensive spice.

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 Crocus to ensure they mature before fall.

Bulb Blooms in Spring Pollinator-friendly Fragrant
Modoc County, CA (Zone 6b) Short season
113 days
Last Spring Frost May 31
113 growing days
First Fall Frost September 21

Modoc County Soil Profile

Soil Type

Loam

Soil pH

5.9-7.4

Drainage

Well Drained

Crocus Planting Risk Windows

Early Start (70% safe) ✓ Fits season (141 days to spare)
Transplant: May 19 🌸 Bloom: Apr 7 – Apr 28
Recommended (50%) ✓ Fits season (134 days to spare)
Transplant: May 31 🌸 Bloom: Apr 19 – May 10
Safe Start (90%) ✓ Fits season (140 days to spare)
Transplant: Jun 19 🌸 Bloom: May 8 – May 29

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 Crocus's growing requirements.

Soil pH

Your soil pH (5.9–7.4) overlaps with Crocus's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Crocus.

Organic Matter

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

How to Plant Crocus

4"
Planting Depth
3"
Between Plants
4"
Between Rows

Fall planting: Sow 6 weeks before your first frost date for a fall harvest.

Succession Planting Crocus

13
successive plantings in your 113-day season

Sow every 1.1 weeks. Last sowing by Sep 01 to harvest before frost.

For a dedicated fall crop, sow by Aug 10.

Crocus Water Budget

Plant needs
0.5″/week
Rainfall provides
1.1″/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 Crocus

Crocus 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 Crocus 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 2.2" 0.7" 1.5" 🚿 Regular watering
Jun 2.2" 0.1" 2.1" 🚿 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 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.

Crocus 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.

Crocus needs ~184 GDD — county provides 1,384 GDD Excellent fit

Crocus Planting Timeline — Modoc County, CA

Crocus Planting Calendar

Activity When Date Range
Bloom June 29 Jun 29 – Jul 20
Fall Sowing August 10 Aug 10 – Aug 24

Plant 4" deep · 3" apart · Rows 4" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April
May
June Bloom
July Bloom
August Fall Sowing
September
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

10–20 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

113 days in Modoc County

Growing Tips for Crocus in Modoc County

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

Your generous 113.0-day season in Modoc County allows multiple plantings of Crocus. Sow every 5.0 days for continuous harvest.

General growing tips

Plant corms 3–4 inches deep and 2–3 inches apart in fall, when soil temperature drops below 60°F. Mass plantings (at least 25 corms per cluster) create the most visual impact. Plant in well-drained soil — corms rot in standing water. Crocus naturalize well under deciduous trees; the tree leafs out after crocus dormancy begins, so light competition is minimal. Squirrels and chipmunks dig corms — plant deeper (4 inches) or use wire mesh baskets in high-predation areas. Allow foliage to die back naturally before mowing lawns. In zones 8a–8b, plant in December with pre-chilled corms for best results.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Crocus in Modoc County, CA?

Modoc County is in Zone 6b with an average last frost of May 31. Plan your Crocus 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.

When should I plant Crocus in Modoc County County, ?

In Modoc County County, , plant Crocus after the last frost (around May 31) and before the first frost (around September 21). Best results when soil holds above 50°F.

What growing zone is Modoc County County, for Crocus?

Modoc County County sits in USDA Zone 6b. Crocus grows reliably in zones 3a through 8b, so it's a good fit here.

Can Crocus grow in Modoc County County's climate?

Yes — Crocus grows well in Modoc County County's temperate climate. Modoc County County averages a 113-day frost-free season, with last frost around May 31 and first frost around September 21.

🌱

Your Modoc County Garden Planner — Free

A 22-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: June 2026.

Sources & credits

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