When to Plant Eggplant in Cache County, UT
Eggplant is a heat-loving solanaceous crop that produces glossy fruits in purple, white, or striped varieties. It requires long, warm growing seasons for best production.
Cache County, Utah is in USDA Zone 5b. The average last spring frost is June 11 and the first fall frost is September 2, giving you a growing season of approximately 83 days.
At an elevation of 6,265 feet, Cache County receives approximately 15.5 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Eggplant to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Eggplant successfully. Mulch heavily to conserve soil moisture.
Cache County Soil Profile
Soil Type
Loam
Soil pH
6.6-8.4
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 Cache County
How your county's soil matches Eggplant's growing requirements.
Soil pH
Your soil pH (6.6–8.4) is more alkaline than Eggplant prefers (5.5–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Cache County is excellent for Eggplant — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Eggplant.
How to Plant Eggplant
How Much Eggplant to Grow
For a family of 4, plant approximately 8 eggplant plants in about 70 sq ft. In Cache County's 83-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Plant Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Eggplant
Eggplant needs approximately 1.1 inches of water per week (4.8" per month). Here's how your county's rainfall compares month by month.
| Month | Eggplant Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.1" | 0" | ❄️ Dormant |
| Feb | — | 0.9" | 0" | ❄️ Dormant |
| Mar | — | 1.3" | 0" | ❄️ Dormant |
| Apr | — | 1.7" | 0" | ❄️ Dormant |
| May | — | 2" | 0" | ❄️ Dormant |
| Jun | 4.8" | 1.1" | 3.7" | 🚿 Regular watering |
| Jul | 4.8" | 1.3" | 3.5" | 🚿 Regular watering |
| Aug | 4.8" | 1.5" | 3.3" | 🚿 Regular watering |
| Sep | 4.8" | 1.3" | 3.5" | 🚿 Regular watering |
| Oct | — | 1.4" | 0" | ❄️ Dormant |
| Nov | — | 1.1" | 0" | ❄️ Dormant |
| Dec | — | 0.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Cache County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Eggplant 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.
Eggplant Planting Timeline — Cache County, UT
Eggplant Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 2 | Apr 2 – Apr 16 |
| Transplant Outdoors | June 25 | Jun 25 – Jul 9 |
| Direct Sow | June 18 | Jun 18 – Jul 9 |
| Harvest | September 3 | Sep 3 – Nov 5 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | — |
| June | Transplant Outdoors Direct Sow |
| July | Transplant Outdoors Direct Sow |
| August | — |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.1"/week · 1-2 times/week
📅 Days to Maturity
65–85 days
🧪 Soil pH
Needs 5.5–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 5b
📆 Growing Season
83 days in Cache County
Growing Tips for Eggplant in Cache County
Direct sow Eggplant outdoors after June 11 in Cache County when soil has warmed and frost danger has passed.
Your 83.0-day growing season in Cache County is tight for Eggplant (65.0-85.0 days to maturity). Start indoors and choose early-maturing varieties.
Common pests for Eggplant in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.
Cache County receives only 16" of rain annually. Eggplant needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 8-10 weeks before last frost. Transplant only after nighttime temperatures stay above 55F. Mulch to retain moisture and warmth around roots.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Eggplant in Other Locations
Frequently Asked Questions
When should I plant Eggplant in Cache County, UT?
Cache County is in Zone 5b with an average last frost of June 11. Plan your Eggplant planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cache County, UT?
Cache County, Utah is in USDA Hardiness Zone 5b. The average last spring frost is June 11 and first fall frost is September 2.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Cache County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.
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