When to Plant Shiso in El Paso County, TX
May to-do list for El Paso County, Texas
We've pulled the most time-sensitive tasks for El Paso County, Texas this May and put them front and centre. Tackle them in order.
-
Begin indoor sowing: shiso
A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.
-
Collect shiso at their peak
If you can't use it all right away, check the food-preservation section of your planner.
Coming up in June — start thinking about
- First harvests: shiso
Shiso (perilla) is a fragrant Japanese herb with large, ruffled leaves in green or purple varieties. It has a unique flavor combining mint, basil, and anise.
El Paso County, Texas is in USDA Zone 8b. The average last spring frost is March 16 and the first fall frost is November 11, giving you a growing season of approximately 240 days.
At an elevation of 3,971 feet, El Paso County receives approximately 35.6 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 107°F, so Shiso may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Shiso will need more frequent watering and organic matter to retain nutrients.
El Paso County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.4-8.5
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 El Paso County
How your county's soil matches Shiso's growing requirements.
Soil pH
Your soil pH (7.4–8.5) is more alkaline than Shiso prefers (5.5–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in El Paso County warms quickly in spring but drains fast. Shiso will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Shiso.
Organic Matter
Organic matter is low (1.1%). Add 2-3 inches of compost before planting Shiso.
How to Plant Shiso
Succession Planting Shiso
Sow every 5.7 weeks. Last sowing by Sep 02 to harvest before frost.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Shiso
Shiso needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Shiso Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.4" | 0" | ❄️ Dormant |
| Feb | — | 1.9" | 0" | ❄️ Dormant |
| Mar | 4.3" | 1.8" | 2.5" | 🚿 Regular watering |
| Apr | 4.3" | 1.1" | 3.2" | 🚿 Regular watering |
| May | 4.3" | 0.8" | 3.5" | 🚿 Regular watering |
| Jun | 4.3" | 1.1" | 3.2" | 🚿 Regular watering |
| Jul | 4.3" | 5.6" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 7.5" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Nov | 4.3" | 1.8" | 2.5" | 🚿 Regular watering |
| Dec | — | 2.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in El Paso County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Shiso 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.
Shiso Planting Timeline — El Paso County, TX
Shiso Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 26 | Jan 26 – Feb 9 |
| Transplant Outdoors | March 30 | Mar 30 – Apr 13 |
| Direct Sow | March 23 | Mar 23 – Apr 13 |
| Harvest | May 25 | May 25 – Jul 20 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors |
| March | Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.5–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 8b
📆 Growing Season
240 days in El Paso County
Growing Tips for Shiso in El Paso County
Direct sow Shiso outdoors after March 16 in El Paso County when soil has warmed and frost danger has passed.
Sandy soil in El Paso County dries quickly — mulch Shiso with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
With summer highs reaching 107°F in El Paso County, provide afternoon shade for Shiso and water deeply in the morning.
General growing tips
Direct sow after last frost or start indoors. Both green and red varieties are available. Pinch tips to encourage bushiness. Self-sows prolifically; deadhead to control.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Shiso in Other Locations
Frequently Asked Questions
When should I plant Shiso in El Paso County, TX?
El Paso County is in Zone 8b with an average last frost of March 16. Plan your Shiso planting based on this frost date — see the calendar above for exact timing.
What planting zone is El Paso County, TX?
El Paso County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 16 and first fall frost is November 11.
Your El Paso County Garden Planner — Free
A 24-page printable planner built for El Paso 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.