When to Plant Lemon Verbena in Riverside County, CA
What to do in May
May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Riverside County, California.
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Pick lemon verbena
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
Looking ahead to June
- First harvests: lemon verbena
Lemon verbena is a deciduous shrub with intensely lemon-scented leaves that retain their aroma when dried. It makes an exceptional tea and adds citrus flavor to dishes.
Riverside County, California is in USDA Zone 10a. The average last spring frost is February 24 and the first fall frost is December 4, giving you a growing season of approximately 283 days.
At an elevation of 1,206 feet, Riverside County receives approximately 15.5 inches of rainfall annually with predominantly loam soil. Summer highs average 102°F, so Lemon Verbena may need afternoon shade and extra watering during peak heat. With low rainfall, drip irrigation is essential for growing Lemon Verbena successfully. Mulch heavily to conserve soil moisture.
Riverside County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.8
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.
Soil Compatibility in Riverside County
How your county's soil matches Lemon Verbena's growing requirements.
Soil pH
Your soil pH (6.2–7.8) overlaps with Lemon Verbena's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in Riverside County is excellent for Lemon Verbena — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.5%). Annual compost additions will help Lemon Verbena.
How to Plant Lemon Verbena
Succession Planting Lemon Verbena
Sow every 6.9 weeks. Last sowing by Sep 05 to harvest before frost.
Plant Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Lemon Verbena
Lemon Verbena needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Lemon Verbena Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.5" | 0" | ❄️ Dormant |
| Feb | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Mar | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Apr | 4.3" | 1.2" | 3.1" | 🚿 Regular watering |
| May | 4.3" | 0.4" | 3.9" | 🚿 Regular watering |
| Jun | 4.3" | 0.1" | 4.2" | 🚿 Regular watering |
| Jul | 4.3" | 0" | 4.3" | 🚿 Regular watering |
| Aug | 4.3" | 0" | 4.3" | 🚿 Regular watering |
| Sep | 4.3" | 0.2" | 4.1" | 🚿 Regular watering |
| Oct | 4.3" | 0.6" | 3.7" | 🚿 Regular watering |
| Nov | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Dec | 4.3" | 2.4" | 1.9" | 💧 Light watering |
Water needs are for active growing months only (Feb–Dec in Riverside County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Lemon Verbena 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.
Lemon Verbena Planting Timeline — Riverside County, CA
Lemon Verbena Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 13 | Jan 13 – Jan 27 |
| Transplant Outdoors | March 3 | Mar 3 – Mar 17 |
| Direct Sow | March 3 | Mar 3 – Mar 24 |
| Harvest | May 5 | May 5 – Jul 14 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | — |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 10a
📆 Growing Season
283 days in Riverside County
Growing Tips for Lemon Verbena in Riverside County
Direct sow Lemon Verbena outdoors after February 24 in Riverside County when soil has warmed and frost danger has passed.
With summer highs reaching 102°F in Riverside County, provide afternoon shade for Lemon Verbena and water deeply in the morning.
Riverside County receives only 16" of rain annually. Lemon Verbena needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Grow in a container in cold climates and bring indoors for winter. Prune back hard in spring. Harvest leaves anytime but flavor peaks just before flowering. Dries well for tea.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Lemon Verbena in Other Locations
Frequently Asked Questions
When should I plant Lemon Verbena in Riverside County, CA?
Riverside County is in Zone 10a with an average last frost of February 24. Plan your Lemon Verbena planting based on this frost date — see the calendar above for exact timing.
What planting zone is Riverside County, CA?
Riverside County, California is in USDA Hardiness Zone 10a. The average last spring frost is February 24 and first fall frost is December 4.
Your Riverside County Garden Planner — Free
A 24-page printable planner built for Riverside County (Zone 10a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.