When to Plant Tarragon in Rockwall County, TX
Top priorities for Rockwall County, Texas gardeners in May
If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.
-
Basket week: tarragon
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
A few tasks this May that'll pay off in June
- First harvests: tarragon
French tarragon is a perennial herb with slender leaves and a distinctive anise-like flavor essential in French cooking. It does not produce viable seed and must be propagated vegetatively.
Rockwall County, Texas is in USDA Zone 8b. The average last spring frost is March 9 and the first fall frost is November 20, giving you a growing season of approximately 256 days.
At an elevation of 74 feet, Rockwall County receives approximately 71.3 inches of rainfall annually with predominantly clay soil. Summer highs average 91°F, providing good warmth for Tarragon during the growing season. Clay soil retains moisture well for Tarragon, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Tarragon root diseases.
Rockwall County Soil Profile
Soil Type
Clay
Soil pH
7.2-8.1
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 Rockwall County
How your county's soil matches Tarragon's growing requirements.
Soil pH
Your soil pH (7.2–8.1) is more alkaline than Tarragon prefers (6.0–7.5). Add sulfur or peat moss to lower pH.
Soil Texture
Heavy clay soil (46% clay) in Rockwall County compacts easily and drains slowly. Amend with compost and avoid working soil when wet.
Organic Matter
Organic matter is moderate (2.7%). Annual compost additions will help Tarragon.
How to Plant Tarragon
Succession Planting Tarragon
Sow every 6.9 weeks. Last sowing by Aug 22 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Tarragon
Tarragon needs approximately 0.4 inches of water per week (1.7" per month). Here's how your county's rainfall compares month by month.
| Month | Tarragon Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2" | 0" | ❄️ Dormant |
| Feb | — | 2.7" | 0" | ❄️ Dormant |
| Mar | 1.7" | 4.5" | 0" | ✅ Rainfall sufficient |
| Apr | 1.7" | 6.7" | 0" | ✅ Rainfall sufficient |
| May | 1.7" | 12.1" | 0" | ✅ Rainfall sufficient |
| Jun | 1.7" | 10" | 0" | ✅ Rainfall sufficient |
| Jul | 1.7" | 9.6" | 0" | ✅ Rainfall sufficient |
| Aug | 1.7" | 9" | 0" | ✅ Rainfall sufficient |
| Sep | 1.7" | 6.7" | 0" | ✅ Rainfall sufficient |
| Oct | 1.7" | 4.1" | 0" | ✅ Rainfall sufficient |
| Nov | 1.7" | 2.3" | 0" | ✅ Rainfall sufficient |
| Dec | — | 1.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Rockwall County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Tarragon 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.
Tarragon Planting Timeline — Rockwall County, TX
Tarragon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | March 16 | Mar 16 – Mar 30 |
| Harvest | May 18 | May 18 – Jul 27 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Transplant Outdoors |
| April | — |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.4"/week · Natural rainfall sufficient
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7.5 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 8b
📆 Growing Season
256 days in Rockwall County
Growing Tips for Tarragon in Rockwall County
Direct sow Tarragon outdoors after March 09 in Rockwall County when soil has warmed and frost danger has passed.
With Rockwall County's clay soil (46% clay), work in 3-4 inches of compost before planting Tarragon. Avoid tilling when soil is wet to prevent compaction.
Common pests for Tarragon in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
With 71" of annual rainfall in Rockwall County, ensure good drainage for Tarragon — excess moisture can promote root rot and fungal diseases.
General growing tips
Purchase plants or divisions as French tarragon does not grow true from seed. Plant in well-drained soil. Divide every 3-4 years to maintain vigor. Harvest tips regularly for best flavor.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Tarragon in Other Locations
Frequently Asked Questions
When should I plant Tarragon in Rockwall County, TX?
Rockwall County is in Zone 8b with an average last frost of March 9. Plan your Tarragon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Rockwall County, TX?
Rockwall County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 9 and first fall frost is November 20.
Your Rockwall County Garden Planner — Free
A 24-page printable planner built for Rockwall County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.