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When to Plant Sweet Potatoes in Kane County, UT

Sweet potatoes are a warm-season root crop that produces nutritious, sweet tubers in orange, white, and purple varieties. They need a long, hot growing season.

Kane County, Utah is in USDA Zone 6a. The average last spring frost is May 13 and the first fall frost is October 7, giving you a growing season of approximately 147 days.

At an elevation of 5,900 feet, Kane County receives approximately 19.5 inches of rainfall annually with predominantly loam soil. Summer highs average 90ยฐF, providing good warmth for Sweet Potatoes during the growing season. With low rainfall, drip irrigation is essential for growing Sweet Potatoes successfully. Mulch heavily to conserve soil moisture.

Kane County, UT (Zone 6a) Short season
147 days
Last Spring Frost May 13
147 growing days
First Fall Frost October 7

Kane County Soil Profile

Soil Type

Loam

Soil pH

6.2-8.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 9 Transplant: May 18 🍅 Harvest: Aug 17 – Oct 5
Recommended (50%) ✗ May not fit
Start indoors: Mar 18 Transplant: May 27 🍅 Harvest: Aug 26 – Oct 14
Safe Start (90%) ✗ May not fit
Start indoors: Apr 11 Transplant: Jun 20 🍅 Harvest: Sep 19 – Nov 7

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 Kane County

How your county's soil matches Sweet Potatoes's growing requirements.

Soil pH

Your soil pH (6.2โ€“8.1) is more alkaline than Sweet Potatoes prefers (5.5โ€“6.5). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Kane County is excellent for Sweet Potatoes โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Sweet Potatoes.

How to Plant Sweet Potatoes

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 695 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Sweet Potatoes

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

Month Sweet Potatoes Needs Rainfall You Supplement Action
Jan โ€” 1.2" 0" โ„๏ธ Dormant
Feb โ€” 1.1" 0" โ„๏ธ Dormant
Mar โ€” 1.9" 0" โ„๏ธ Dormant
Apr โ€” 2.3" 0" โ„๏ธ Dormant
May 4.3" 2.2" 2.1" ๐Ÿ’ง Light watering
Jun 4.3" 1.3" 3" ๐Ÿšฟ Regular watering
Jul 4.3" 1.5" 2.8" ๐Ÿšฟ Regular watering
Aug 4.3" 2.2" 2.1" ๐Ÿ’ง Light watering
Sep 4.3" 1.5" 2.8" ๐Ÿšฟ Regular watering
Oct 4.3" 1.6" 2.7" ๐Ÿšฟ Regular watering
Nov โ€” 1.4" 0" โ„๏ธ Dormant
Dec โ€” 1.3" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Kane County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Sweet Potatoes 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" โ€” every day above 50ยฐF 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.

Sweet Potatoes needs ~1,838 GDD — county provides 2,572 GDD Excellent fit

Sweet Potatoes Planting Timeline โ€” Kane County, UT

Sweet Potatoes Planting Calendar

Activity When Date Range
Start Indoors March 18 Mar 18 โ€“ Apr 1
Transplant Outdoors May 27 May 27 โ€“ Jun 10
Direct Sow May 20 May 20 โ€“ Jun 10
Harvest August 26 Aug 26 โ€“ Oct 14

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April Start Indoors
May Transplant Outdoors Direct Sow
June Transplant Outdoors Direct Sow
July โ€”
August Harvest
September Harvest
October Harvest
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

90โ€“120 days

๐Ÿงช Soil pH

Needs 5.5โ€“6.5 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

147 days in Kane County

Growing Tips for Sweet Potatoes in Kane County

Direct sow Sweet Potatoes outdoors after May 13 in Kane County when soil has warmed and frost danger has passed.

Kane County receives only 20" of rain annually. Sweet Potatoes needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Plant slips (rooted sprouts) after soil is thoroughly warm. Build raised mounds for better root development. Cure harvested roots at 80-85F for 10 days to develop sweetness.

Companion Planting

Good Companions

Avoid Planting Near

  • Squash Summer

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sweet Potatoes in Kane County, UT?

Kane County is in Zone 6a with an average last frost of May 13. Plan your Sweet Potatoes planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Kane County, UT?

Kane County, Utah is in USDA Hardiness Zone 6a. The average last spring frost is May 13 and first fall frost is October 7.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Kane County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

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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 Kane County, UT. Local conditions may vary. Last updated: April 2026.