When to Plant Sorrel in Union County, TN
Top priorities for Union County, Tennessee gardeners in May
May is a pivotal month for Union County, Tennessee gardens. Focus on these tasks first and you'll set up the rest of the season for success.
-
Start sorrel indoors
Your window is short. These crops want several weeks of indoor growth before they go outside.
-
Basket week: sorrel
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
June prep starts now
- First harvests: sorrel
Sorrel is a perennial herb with tangy, lemon-flavored arrow-shaped leaves. It is one of the first greens to emerge in spring and is used in soups and salads.
Union County, Tennessee is in USDA Zone 7b. The average last spring frost is April 10 and the first fall frost is October 29, giving you a growing season of approximately 202 days.
At an elevation of 1,122 feet, Union County receives approximately 50.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Sorrel during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sorrel root diseases.
Union County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-6.6
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.
Soil Compatibility in Union County
How your county's soil matches Sorrel's growing requirements.
Soil pH
Your soil pH (5.8–6.6) is within Sorrel's preferred range (5.5–7.0).
Soil Texture
The silt loam soil in Union County is excellent for Sorrel — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.9%). Annual compost additions will help Sorrel.
How to Plant Sorrel
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Sorrel
Sow every 4.6 weeks. Last sowing by Aug 30 to harvest before frost.
For a dedicated fall crop, sow by Aug 20.
Plant Water Budget
Monthly Watering Guide for Sorrel
Sorrel needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Sorrel Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.8" | 0" | ❄️ Dormant |
| Feb | — | 3.4" | 0" | ❄️ Dormant |
| Mar | — | 5.2" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| May | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Jun | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 5.6" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Oct | 4.3" | 3.3" | 1" | 💧 Light watering |
| Nov | — | 3.4" | 0" | ❄️ Dormant |
| Dec | — | 4.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Union County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sorrel 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" — every day above 50°F 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.
Sorrel Planting Timeline — Union County, TN
Sorrel Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 6 | Mar 6 – Mar 20 |
| Transplant Outdoors | April 3 | Apr 3 – Apr 17 |
| Direct Sow | March 27 | Mar 27 – Apr 17 |
| Harvest | May 15 | May 15 – Jul 17 |
| Fall Sowing | August 20 | Aug 20 – Sep 3 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
40–60 days
🧪 Soil pH
Needs 5.5–7 · Your soil: ideal
🗺️ USDA Zone
Zone 7b
📆 Growing Season
202 days in Union County
Growing Tips for Sorrel in Union County
Direct sow Sorrel outdoors after April 10 in Union County when soil has warmed and frost danger has passed.
Your generous 202.0-day season in Union County allows multiple plantings of Sorrel. Sow every 20.0 days for continuous harvest.
General growing tips
Direct sow in early spring or fall. Remove flower stalks promptly to encourage leaf production. Divide clumps every 3-4 years. Young leaves have the best flavor.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Sorrel in Other Locations
Frequently Asked Questions
When should I plant Sorrel in Union County, TN?
Union County is in Zone 7b with an average last frost of April 10. Plan your Sorrel planting based on this frost date — see the calendar above for exact timing.
What planting zone is Union County, TN?
Union County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is April 10 and first fall frost is October 29.
Your Union County Garden Planner — Free
A 24-page printable planner built for Union County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.