When to Plant Lentils in Union County, IA
Lentils are an ancient pulse crop producing small, lens-shaped seeds packed with protein and iron. They grow on short, bushy plants and are surprisingly easy to cultivate.
Union County, Iowa is in USDA Zone 5a. The average last spring frost is April 23 and the first fall frost is October 11, giving you a growing season of approximately 171 days.
At an elevation of 1,311 feet, Union County receives approximately 39 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Lentils to ensure they mature before fall.
Union County Soil Profile
Soil Type
Silt Loam
Soil pH
6.3-7.3
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
Lentils Planting Timeline — Union County, IA
Lentils Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 19 | Mar 19 – Apr 2 |
| Transplant Outdoors | April 23 | Apr 23 – May 7 |
| Direct Sow | April 9 | Apr 9 – Apr 30 |
| Fall Sowing | August 2 | Aug 2 – Aug 16 |
| Harvest | July 16 | Jul 16 – Aug 27 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Low — drought tolerant
Days to Maturity
80–110 days
Soil pH
6 – 8
USDA Zone
Zone 5a
Growing Season
171 days
Growing Tips for Union County
Direct sow in early spring as lentils tolerate frost. Provide short supports as plants tend to lodge. Harvest when lower pods turn brown. Pull entire plants and dry in bundles.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Lentils in Other Locations
Frequently Asked Questions
When should I plant Lentils in Union County, IA?
Union County is in Zone 5a with an average last frost of April 23. Plan your Lentils planting based on this frost date — see the calendar above for exact timing.
What planting zone is Union County, IA?
Union County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 23 and first fall frost is October 11.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Union County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.
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