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When to Plant Hostas in Crook County, OR

Crook County, Oregon Zone 6a June

Your June planting checklist for Crook County, Oregon

Here's what deserves your attention in Crook County, Oregon this month. Everything below is tailored to Zone 6a and timed around your local frost dates.

Avg. last frost June 9
Avg. first frost September 19
Soil temp (4") 70°F
Watering Critical
Pest pressure High
Daylight 15.3 hrs
  1. Plant out hostas

    Pick a cloudy afternoon or evening to plant. Less transplant shock, and your seedlings will barely blink.

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Hostas (Hosta spp.) are the undisputed kings of the shade garden, grown primarily for their spectacular mounded foliage in shades of deep green, blue-green, gold, and variegated combinations. Originating in East Asia (Japan, China, Korea), hostas form dense, long-lived clumps that reliably return year after year with minimal care. In summer, tall scapes of lavender or white tubular flowers rise above the foliage — some cultivars (notably H. plantaginea hybrids) are notably fragrant. Extremely adaptable in moist, well-drained soil with consistent shade to part shade.

Crook County, Oregon is in USDA Zone 6a. The average last spring frost is June 9 and the first fall frost is September 19, giving you a growing season of approximately 102 days.

At an elevation of 2,233 feet, Crook County receives approximately 21 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Hostas during the growing season.

Perennial Blooms in Summer Pollinator-friendly
Crook County, OR (Zone 6a) Short season
102 days
Last Spring Frost June 9
102 growing days
First Fall Frost September 19
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Crook County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.7

Drainage

Well Drained

Hostas Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 21 Transplant: Jun 6 🌸 Bloom: Aug 22 – Dec 5
Recommended (50%) ✗ May not fit
Start indoors: Mar 31 Transplant: Jun 16 🌸 Bloom: Sep 1 – Dec 15
Safe Start (90%) ✗ May not fit
Start indoors: Apr 13 Transplant: Jun 29 🌸 Bloom: Sep 14 – Dec 28

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 Crook County

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

Soil pH

Your soil pH (5.7–6.7) overlaps with Hostas's range (6.0–7.5), though not a perfect match.

Soil Texture

The silt loam soil in Crook County is excellent for Hostas — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (5.6%) — Hostas will thrive.

How to Plant Hostas

1"
Planting Depth
24"
Between Plants
30"
Between Rows

Hostas Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 147 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Hostas

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

Month Hostas Needs Rainfall You Supplement Action
Jan 3.4" 0" ❄️ Dormant
Feb 2.2" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 1.5" 0" ❄️ Dormant
May 1.2" 0" ❄️ Dormant
Jun 4.3" 0.9" 3.4" 🚿 Regular watering
Jul 4.3" 0.3" 4" 🚿 Regular watering
Aug 4.3" 0.4" 3.9" 🚿 Regular watering
Sep 4.3" 1" 3.3" 🚿 Regular watering
Oct 1.6" 0" ❄️ Dormant
Nov 3.1" 0" ❄️ Dormant
Dec 3.1" 0" ❄️ Dormant

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

Hostas 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.

Hostas needs ~1,031 GDD — county provides 1,402 GDD Excellent fit

Hostas Planting Timeline — Crook County, OR

Hostas Planting Calendar

Activity When Date Range
Start Indoors March 31 Mar 31 – Apr 14
Transplant Outdoors June 16 Jun 16 – Jun 30
Bloom September 1 Sep 1 – Dec 15

Plant 1" deep · 24" apart · Rows 30" apart

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

102 days in Crook County

Growing Tips for Hostas in Crook County

Direct sow Hostas outdoors after June 09 in Crook County when soil has warmed and frost danger has passed.

Your 102.0-day growing season in Crook County is tight for Hostas (60.0-90.0 days to maturity). Start indoors and choose early-maturing varieties.

Crook County receives only 21" of rain annually. Hostas needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Plant bare-root crowns or divisions in early spring just as new growth emerges, or in fall at least 6 weeks before hard freeze. Choose a site with morning sun and afternoon shade in Zones 6+; deeper shade is acceptable but reduces vigor and bloom. Keep consistently moist but never waterlogged. Apply a 2–3 inch mulch layer to conserve moisture and suppress weeds. Slugs are the primary pest — use iron phosphate bait if damage is significant. Deer will browse hostas heavily in most regions; protect with fencing or repellents. Divide every 3–5 years in spring to rejuvenate. Fall planting (Zones 4+) is equally effective as spring planting when soil stays workable. Year 2+ plants reach full size and flower most reliably; first-year divisions may produce limited flower spikes.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Hostas in Crook County, OR?

Crook County is in Zone 6a with an average last frost of June 9. Plan your Hostas planting based on this frost date — see the calendar above for exact timing.

What planting zone is Crook County, OR?

Crook County, Oregon is in USDA Hardiness Zone 6a. The average last spring frost is June 9 and first fall frost is September 19.

🌱

Your Crook County Garden Planner — Free

A 22-page printable planner built for Crook County (Zone 6a). 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 Crook County, OR. 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.