When to Plant Cilantro in Knox County, TN
What to do in May
A quick May briefing for Knox County, Tennessee gardeners — what's urgent, what's next, and what can wait.
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Time to start cilantro inside
Label every cell. You will absolutely forget which is which otherwise.
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It's harvest week for cilantro
The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.
June will be here before you know it — start on
- First harvests: cilantro
Cilantro is a dual-purpose herb providing fresh leaves (cilantro) and dried seeds (coriander). It bolts quickly in heat, producing flowers beloved by beneficial insects.
Knox 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 2,448 feet, Knox County receives approximately 47.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 93°F, providing good warmth for Cilantro during the growing season.
Knox County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-7
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 Knox County
How your county's soil matches Cilantro's growing requirements.
Soil pH
Your soil pH (5.7–7.0) overlaps with Cilantro's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Knox County is excellent for Cilantro — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.0%). Annual compost additions will help Cilantro.
How to Plant Cilantro
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Cilantro
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
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Cilantro
Cilantro needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Cilantro Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.1" | 0" | ❄️ Dormant |
| Feb | — | 4.1" | 0" | ❄️ Dormant |
| Mar | — | 4.7" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 3.8" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 5.2" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.8" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.5" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3.7" | 0" | ❄️ Dormant |
| Dec | — | 3.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Knox County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Cilantro 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.
Cilantro Planting Timeline — Knox County, TN
Cilantro 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
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
40–60 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 7b
📆 Growing Season
202 days in Knox County
Growing Tips for Cilantro in Knox County
Direct sow Cilantro outdoors after April 10 in Knox County when soil has warmed and frost danger has passed.
Summer highs in Knox County reach 93°F — grow Cilantro as a spring or fall crop. Use shade cloth if planting in summer.
Your generous 202.0-day season in Knox County allows multiple plantings of Cilantro. Sow every 20.0 days for continuous harvest.
Common pests for Cilantro in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.
General growing tips
Succession sow every 2-3 weeks. Provide afternoon shade in warm weather. Harvest leaves before flowering or allow some plants to go to seed for coriander and self-sowing.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Cilantro in Other Locations
Frequently Asked Questions
When should I plant Cilantro in Knox County, TN?
Knox County is in Zone 7b with an average last frost of April 10. Plan your Cilantro planting based on this frost date — see the calendar above for exact timing.
What planting zone is Knox County, TN?
Knox County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is April 10 and first fall frost is October 29.
Your Knox County Garden Planner — Free
A 24-page printable planner built for Knox 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.