When to Plant Lemon Balm in Douglas County, CO
Lemon balm is a vigorous perennial herb with bright green, lemon-scented leaves. It makes a refreshing tea and is easy to grow but can spread aggressively.
Douglas County, Colorado is in USDA Zone 5b. The average last spring frost is May 22 and the first fall frost is September 20, giving you a growing season of approximately 121 days.
At an elevation of 7,421 feet, Douglas County receives approximately 12.9 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Lemon Balm during the growing season. With low rainfall, drip irrigation is essential for growing Lemon Balm successfully. Mulch heavily to conserve soil moisture.
Douglas County Soil Profile
Soil Type
Loam
Soil pH
6.7-8.4
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 Douglas County
How your county's soil matches Lemon Balm's growing requirements.
Soil pH
Your soil pH (6.7–8.4) is more alkaline than Lemon Balm prefers (5.5–7.5). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Douglas County is excellent for Lemon Balm — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Lemon Balm.
How to Plant Lemon Balm
Succession Planting Lemon Balm
Sow every 6.9 weeks. Last sowing by Jul 12 to harvest before frost.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Lemon Balm
Lemon Balm 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 | Lemon Balm Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1" | 0" | ❄️ Dormant |
| Feb | — | 0.8" | 0" | ❄️ Dormant |
| Mar | — | 1.1" | 0" | ❄️ Dormant |
| Apr | — | 1.3" | 0" | ❄️ Dormant |
| May | 2.2" | 1.4" | 0.8" | 💧 Light watering |
| Jun | 2.2" | 1" | 1.2" | 🚿 Regular watering |
| Jul | 2.2" | 1" | 1.2" | 🚿 Regular watering |
| Aug | 2.2" | 1.4" | 0.8" | 💧 Light watering |
| Sep | 2.2" | 1.1" | 1.1" | 🚿 Regular watering |
| Oct | — | 1.1" | 0" | ❄️ Dormant |
| Nov | — | 1" | 0" | ❄️ Dormant |
| Dec | — | 0.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Douglas County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Lemon Balm 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 Balm Planting Timeline — Douglas County, CO
Lemon Balm Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 29 | May 29 – Jun 12 |
| Harvest | July 31 | Jul 31 – Sep 18 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | Transplant Outdoors |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.5"/week · Only during dry spells
📅 Days to Maturity
60–70 days
🧪 Soil pH
Needs 5.5–7.5 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 5b
📆 Growing Season
121 days in Douglas County
Growing Tips for Lemon Balm in Douglas County
Direct sow Lemon Balm outdoors after May 22 in Douglas County when soil has warmed and frost danger has passed.
General growing tips
Start from seed, cuttings, or divisions. Contain in pots or use barriers to prevent spreading. Harvest frequently to keep plants bushy and prevent flowering.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Lemon Balm in Other Locations
Frequently Asked Questions
When should I plant Lemon Balm in Douglas County, CO?
Douglas County is in Zone 5b with an average last frost of May 22. Plan your Lemon Balm planting based on this frost date — see the calendar above for exact timing.
What planting zone is Douglas County, CO?
Douglas County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 22 and first fall frost is September 20.
Plan Your Garden with Confidence
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