When to Plant Ground Cherry in King County, WA
Ground cherries produce small, sweet, tropical-tasting berries enclosed in papery husks. They are related to tomatillos and cape gooseberries and self-sow readily.
King County, Washington is in USDA Zone 8b. The average last spring frost is April 7 and the first fall frost is October 30, giving you a growing season of approximately 206 days.
At an elevation of 258 feet, King County receives approximately 37.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Ground Cherry during the growing season.
King County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-6.4
Drainage
Well Drained
Plant Planting Risk Windows
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 Ground Cherry's growing requirements.
Soil pH
Your soil pH (5.7–6.4) overlaps with Ground Cherry's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in King County is excellent for Ground Cherry — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.5%) — Ground Cherry will thrive.
How to Plant Ground Cherry
Succession Planting Ground Cherry
Sow every 7.4 weeks. Last sowing by Aug 11 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Ground Cherry
Ground Cherry needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Ground Cherry Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 5.9" | 0" | ❄️ Dormant |
| Feb | — | 4.5" | 0" | ❄️ Dormant |
| Mar | — | 3.4" | 0" | ❄️ Dormant |
| Apr | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| May | 4.3" | 2" | 2.3" | 🚿 Regular watering |
| Jun | 4.3" | 1.3" | 3" | 🚿 Regular watering |
| Jul | 4.3" | 0.6" | 3.7" | 🚿 Regular watering |
| Aug | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Sep | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Oct | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Nov | — | 5.6" | 0" | ❄️ Dormant |
| Dec | — | 5.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in King County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Ground Cherry 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.
Ground Cherry Planting Timeline — King County, WA
Ground Cherry Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 28 | Apr 28 – May 12 |
| Harvest | July 7 | Jul 7 – Sep 1 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
65–80 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
206 days in King County
Growing Tips for Ground Cherry in King County
Direct sow Ground Cherry outdoors after April 07 in King County when soil has warmed and frost danger has passed.
Common pests for Ground Cherry in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 6-8 weeks before last frost. Let fruits fall to the ground naturally when ripe inside their husks. The husk turns brown and papery when the fruit is ready.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Ground Cherry in Other Locations
Frequently Asked Questions
When should I plant Ground Cherry in King County, WA?
King County is in Zone 8b with an average last frost of April 7. Plan your Ground Cherry planting based on this frost date — see the calendar above for exact timing.
What planting zone is King County, WA?
King County, Washington is in USDA Hardiness Zone 8b. The average last spring frost is April 7 and first fall frost is October 30.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help King County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.
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