When to Plant Lemon Balm in Rio Grande County, CO
April in the garden — Rio Grande County, Colorado
April rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Rio Grande County, Colorado.
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.
Rio Grande County, Colorado is in USDA Zone 4b. The average last spring frost is May 31 and the first fall frost is September 19, giving you a growing season of approximately 111 days.
At an elevation of 6,254 feet, Rio Grande County receives approximately 15.8 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Lemon Balm to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Lemon Balm successfully. Mulch heavily to conserve soil moisture.
Rio Grande County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.8
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 Rio Grande County
How your county's soil matches Lemon Balm's growing requirements.
Soil pH
Your soil pH (6.5–7.8) overlaps with Lemon Balm's range (5.5–7.5), though not a perfect match.
Soil Texture
The loam soil in Rio Grande County is excellent for Lemon Balm — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Lemon Balm.
Organic Matter
Organic matter is moderate (2.7%). 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 11 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 | — | 1.1" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 1.5" | 0" | ❄️ Dormant |
| Apr | — | 1.5" | 0" | ❄️ Dormant |
| May | 2.2" | 2" | 0.2" | 💧 Light watering |
| Jun | 2.2" | 1" | 1.2" | 🚿 Regular watering |
| Jul | 2.2" | 1.4" | 0.8" | 💧 Light watering |
| Aug | 2.2" | 1.9" | 0.3" | 💧 Light watering |
| Sep | 2.2" | 1.4" | 0.8" | 💧 Light watering |
| Oct | — | 1.2" | 0" | ❄️ Dormant |
| Nov | — | 0.9" | 0" | ❄️ Dormant |
| Dec | — | 1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Rio Grande 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 — Rio Grande County, CO
Lemon Balm Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | June 7 | Jun 7 – Jun 21 |
| Harvest | August 9 | Aug 9 – Sep 27 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | — |
| June | Transplant Outdoors |
| July | — |
| 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: acceptable
🗺️ USDA Zone
Zone 4b
📆 Growing Season
111 days in Rio Grande County
Growing Tips for Lemon Balm in Rio Grande County
Direct sow Lemon Balm outdoors after May 31 in Rio Grande 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 Rio Grande County, CO?
Rio Grande County is in Zone 4b with an average last frost of May 31. Plan your Lemon Balm planting based on this frost date — see the calendar above for exact timing.
What planting zone is Rio Grande County, CO?
Rio Grande County, Colorado is in USDA Hardiness Zone 4b. The average last spring frost is May 31 and first fall frost is September 19.
Your Rio Grande County Garden Planner — Free
A 24-page printable planner built for Rio Grande County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.