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When to Plant Crocus in King County, TX

King County, Texas Zone 8a June

Top priorities for King County, Texas gardeners in June

We've pulled the most time-sensitive tasks for King County, Texas this June and put them front and centre. Tackle them in order.

Avg. last frost March 31
Avg. first frost November 7
Soil temp (4") 71°F
Watering High
Pest pressure High
Daylight 14.2 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.

King County, Texas is in USDA Zone 8a. The average last spring frost is March 31 and the first fall frost is November 7, giving you a growing season of approximately 221 days.

At an elevation of 3,170 feet, King County receives approximately 60.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 99°F, so Crocus may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Crocus will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Crocus root diseases.

Bulb Blooms in Spring Pollinator-friendly Fragrant
King County, TX (Zone 8a) Long season
221 days
Last Spring Frost March 31
221 growing days
First Fall Frost November 7

King County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.8-8.4

Drainage

Well Drained

Crocus Planting Risk Windows

Early Start (70% safe) ✓ Fits season (229 days to spare)
Transplant: Mar 23 🌸 Bloom: Feb 23 – Mar 16
Recommended (50%) ✓ Fits season (228 days to spare)
Transplant: Mar 31 🌸 Bloom: Mar 3 – Mar 24
Safe Start (90%) ✓ Fits season (228 days to spare)
Transplant: Apr 15 🌸 Bloom: Mar 18 – Apr 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 King County

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

Soil pH

Your soil pH (7.8–8.4) is more alkaline than Crocus prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is low (1.1%). Add 2-3 inches of compost before planting Crocus.

How to Plant Crocus

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

Fall planting: Sow 4 weeks before your first frost date for a fall harvest.

Succession Planting Crocus

27
successive plantings in your 221-day season

Sow every 1.1 weeks. Last sowing by Oct 18 to harvest before frost.

For a dedicated fall crop, sow by Oct 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 6/10 — 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 4.7" 0" ❄️ Dormant
Feb 3.2" 0" ❄️ Dormant
Mar 2.2" 3.9" 0" ✅ Rainfall sufficient
Apr 2.2" 2.3" 0" ✅ Rainfall sufficient
May 2.2" 1.5" 0.7" 💧 Light watering
Jun 2.2" 2.2" 0" ✅ Rainfall sufficient
Jul 2.2" 10.4" 0" ✅ Rainfall sufficient
Aug 2.2" 11.5" 0" ✅ Rainfall sufficient
Sep 2.2" 8.1" 0" ✅ Rainfall sufficient
Oct 2.2" 5.7" 0" ✅ Rainfall sufficient
Nov 2.2" 3" 0" ✅ Rainfall sufficient
Dec 3.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in King 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 ~364 GDD — county provides 5,359 GDD Excellent fit

Crocus Planting Timeline — King County, TX

Crocus Planting Calendar

Activity When Date Range
Bloom September 12 Sep 12 – Oct 3
Fall Sowing October 10 Oct 10 – Oct 24

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

Month-by-Month Timeline

MonthActivities
January
February
March
April
May
June
July
August
September Bloom
October Fall Sowing Bloom
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: too_alkaline

🗺️ USDA Zone

Zone 8a

📆 Growing Season

221 days in King County

Growing Tips for Crocus in King County

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

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

With summer highs reaching 99°F in King County, provide afternoon shade for Crocus and water deeply in the morning.

Your generous 221.0-day season in King 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 King County, TX?

King County is in Zone 8a with an average last frost of March 31. Plan your Crocus planting based on this frost date — see the calendar above for exact timing.

What planting zone is King County, TX?

King County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 31 and first fall frost is November 7.

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Your King County Garden Planner — Free

A 22-page printable planner built for King County (Zone 8a). 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 King County, TX. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.