When to Plant Rhubarb in Grainger County, TN
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.
Grainger County, Tennessee is in USDA Zone 7a. The average last spring frost is April 15 and the first fall frost is October 22, giving you a growing season of approximately 190 days.
At an elevation of 3,009 feet, Grainger County receives approximately 49.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 92°F, providing good warmth for Rhubarb during the growing season.
Grainger County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-6.8
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
Rhubarb Planting Timeline — Grainger County, TN
Rhubarb Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 6 | May 6 – May 20 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| 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 7a
Growing Season
190 days
Growing Tips for Grainger 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 Grainger County, TN?
Grainger County is in Zone 7a with an average last frost of April 15. Plan your Rhubarb planting based on this frost date — see the calendar above for exact timing.
What planting zone is Grainger County, TN?
Grainger County, Tennessee is in USDA Hardiness Zone 7a. The average last spring frost is April 15 and first fall frost is October 22.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Grainger County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.
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