When to Plant Leeks in Salt Lake County, UT
Leeks are a mild, sweet allium that produces long white shanks. They are more refined than onions and are a key ingredient in soups, stews, and gratins.
Salt Lake County, Utah is in USDA Zone 6b. The average last spring frost is May 6 and the first fall frost is October 10, giving you a growing season of approximately 157 days.
At an elevation of 4,960 feet, Salt Lake County receives approximately 12.2 inches of rainfall annually with predominantly loam soil. Summer highs average 88°F, providing good warmth for Leeks during the growing season. With low rainfall, drip irrigation is essential for growing Leeks successfully. Mulch heavily to conserve soil moisture.
Salt Lake County Soil Profile
Soil Type
Loam
Soil pH
6.7-8.3
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.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Leeks Planting Timeline — Salt Lake County, UT
Leeks Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 1 | Apr 1 – Apr 15 |
| Transplant Outdoors | May 6 | May 6 – May 20 |
| Direct Sow | April 22 | Apr 22 – May 13 |
| Fall Sowing | August 1 | Aug 1 – Aug 15 |
| Harvest | August 5 | Aug 5 – Oct 21 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | — |
| August | Fall Sowing Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
90–150 days
Soil pH
6 – 7
USDA Zone
Zone 6b
Growing Season
157 days
Growing Tips for Salt Lake County
Start seeds indoors 10-12 weeks before last frost. Transplant into trenches and hill soil around stems as they grow to increase the white portion. Harvest as needed.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Leeks in Other Locations
Frequently Asked Questions
When should I plant Leeks in Salt Lake County, UT?
Salt Lake County is in Zone 6b with an average last frost of May 6. Plan your Leeks planting based on this frost date — see the calendar above for exact timing.
What planting zone is Salt Lake County, UT?
Salt Lake County, Utah is in USDA Hardiness Zone 6b. The average last spring frost is May 6 and first fall frost is October 10.
Plan Your Garden with Confidence
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