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When to Plant Lemon Balm in Skamania County, WA

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.

Skamania County, Washington is in USDA Zone 7a. The average last spring frost is April 18 and the first fall frost is October 19, giving you a growing season of approximately 184 days.

At an elevation of 16 feet, Skamania County receives approximately 43 inches of rainfall annually with predominantly silt loam soil. Summer highs average 79ยฐF, so choose short-season varieties of Lemon Balm to ensure they mature before fall.

Skamania County, WA (Zone 7a) Moderate season
184 days
Last Spring Frost April 18
184 growing days
First Fall Frost October 19

Skamania County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (63 days to spare)
Transplant: Apr 19 🍅 Harvest: Jun 21 – Aug 9
Recommended (50%) ✓ Fits season (65 days to spare)
Transplant: Apr 25 🍅 Harvest: Jun 27 – Aug 15
Safe Start (90%) ✓ Fits season (73 days to spare)
Transplant: May 17 🍅 Harvest: Jul 19 – Sep 6

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 Skamania County

How your county's soil matches Lemon Balm's growing requirements.

Soil pH

Your soil pH (5.6โ€“6.2) is within Lemon Balm's preferred range (5.5โ€“7.5).

Soil Texture

The silt loam soil in Skamania County is excellent for Lemon Balm โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (5.0%) โ€” Lemon Balm will thrive.

How to Plant Lemon Balm

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Lemon Balm

3
successive plantings in your 184-day season

Sow every 6.9 weeks. Last sowing by Aug 10 to harvest before frost.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

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 โ€” 6.5" 0" โ„๏ธ Dormant
Feb โ€” 4.3" 0" โ„๏ธ Dormant
Mar โ€” 3.8" 0" โ„๏ธ Dormant
Apr 2.2" 3.6" 0" โœ… Rainfall sufficient
May 2.2" 2.1" 0.1" ๐Ÿ’ง Light watering
Jun 2.2" 1.7" 0.5" ๐Ÿ’ง Light watering
Jul 2.2" 0.7" 1.5" ๐Ÿšฟ Regular watering
Aug 2.2" 0.7" 1.5" ๐Ÿšฟ Regular watering
Sep 2.2" 1.8" 0.4" ๐Ÿ’ง Light watering
Oct 2.2" 3.3" 0" โœ… Rainfall sufficient
Nov โ€” 7.4" 0" โ„๏ธ Dormant
Dec โ€” 7.1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Skamania County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 needs ~601 GDD — county provides 1,702 GDD Excellent fit

Lemon Balm Planting Timeline โ€” Skamania County, WA

Lemon Balm Planting Calendar

Activity When Date Range
Transplant Outdoors April 25 Apr 25 โ€“ May 9
Harvest June 27 Jun 27 โ€“ Aug 15

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Transplant Outdoors
May Transplant Outdoors
June Harvest
July Harvest
August Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

60โ€“70 days

๐Ÿงช Soil pH

Needs 5.5โ€“7.5 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

184 days in Skamania County

Growing Tips for Lemon Balm in Skamania County

Direct sow Lemon Balm outdoors after April 18 in Skamania 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 →

Frequently Asked Questions

When should I plant Lemon Balm in Skamania County, WA?

Skamania County is in Zone 7a with an average last frost of April 18. Plan your Lemon Balm planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Skamania County, WA?

Skamania County, Washington is in USDA Hardiness Zone 7a. The average last spring frost is April 18 and first fall frost is October 19.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Skamania County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Skamania County, WA. Local conditions may vary. Last updated: April 2026.