When to Plant Rhubarb in Harper County, KS
Rhubarb is a long-lived perennial vegetable grown for its tart, colorful stalks. Only the stalks are edible as the leaves contain toxic oxalic acid.
Harper County, Kansas is in USDA Zone 6b. The average last spring frost is April 9 and the first fall frost is October 27, giving you a growing season of approximately 201 days.
At an elevation of 745 feet, Harper County receives approximately 27.7 inches of rainfall annually with predominantly loam soil. Summer highs average 88°F, providing good warmth for Rhubarb during the growing season.
Harper County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.8
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
Rhubarb Planting Timeline — Harper County, KS
Rhubarb Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 30 | Apr 30 – May 14 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | — |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
365–730 days
Soil pH
6 – 7
USDA Zone
Zone 6b
Growing Season
201 days
Growing Tips for Harper County
Plant crowns in early spring in rich, well-drained soil. Do not harvest stalks the first year. Pull (do not cut) stalks at harvest to avoid introducing rot.
Companion Planting
Good Companions
Level Up Your Garden
Rhubarb in Other Locations
Frequently Asked Questions
When should I plant Rhubarb in Harper County, KS?
Harper County is in Zone 6b with an average last frost of April 9. Plan your Rhubarb planting based on this frost date — see the calendar above for exact timing.
What planting zone is Harper County, KS?
Harper County, Kansas is in USDA Hardiness Zone 6b. The average last spring frost is April 9 and first fall frost is October 27.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Harper County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.
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