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When to Plant Borage in Arlington County, VA

Borage is a self-seeding annual herb with star-shaped blue flowers that attract pollinators. Its leaves have a cucumber-like flavor and the flowers are edible.

Arlington County, Virginia is in USDA Zone 7a. The average last spring frost is April 10 and the first fall frost is October 31, giving you a growing season of approximately 204 days.

At an elevation of 284 feet, Arlington County receives approximately 46.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 92ยฐF, providing good warmth for Borage during the growing season.

Arlington County, VA (Zone 7a) Long season
204 days
Last Spring Frost April 10
204 growing days
First Fall Frost October 31

Arlington County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (106 days to spare)
Start indoors: Feb 25 Transplant: Mar 25 🍅 Harvest: May 20 – Jul 8
Recommended (50%) ✓ Fits season (106 days to spare)
Start indoors: Mar 6 Transplant: Apr 3 🍅 Harvest: May 29 – Jul 17
Safe Start (90%) ✓ Fits season (106 days to spare)
Start indoors: Mar 22 Transplant: Apr 19 🍅 Harvest: Jun 14 – Aug 2

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 Arlington County

How your county's soil matches Borage's growing requirements.

Soil pH

Your soil pH (5.3โ€“6.8) overlaps with Borage's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.9%). Annual compost additions will help Borage.

How to Plant Borage

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

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Borage

4
successive plantings in your 204-day season

Sow every 5.7 weeks. Last sowing by Sep 01 to harvest before frost.

For a dedicated fall crop, sow by Aug 22.

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 Borage

Borage 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 Borage Needs Rainfall You Supplement Action
Jan โ€” 3.5" 0" โ„๏ธ Dormant
Feb โ€” 3.8" 0" โ„๏ธ Dormant
Mar โ€” 5" 0" โ„๏ธ Dormant
Apr 2.2" 3.4" 0" โœ… Rainfall sufficient
May 2.2" 3.3" 0" โœ… Rainfall sufficient
Jun 2.2" 3.9" 0" โœ… Rainfall sufficient
Jul 2.2" 4.5" 0" โœ… Rainfall sufficient
Aug 2.2" 4.9" 0" โœ… Rainfall sufficient
Sep 2.2" 4" 0" โœ… Rainfall sufficient
Oct 2.2" 2.7" 0" โœ… Rainfall sufficient
Nov โ€” 3.5" 0" โ„๏ธ Dormant
Dec โ€” 3.8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Arlington County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Borage 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.

Borage needs ~1,045 GDD — county provides 3,876 GDD Excellent fit

Borage Planting Timeline โ€” Arlington County, VA

Borage Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 โ€“ Mar 20
Transplant Outdoors April 3 Apr 3 โ€“ Apr 17
Direct Sow March 27 Mar 27 โ€“ Apr 17
Harvest May 29 May 29 โ€“ Jul 17
Fall Sowing August 22 Aug 22 โ€“ Sep 5

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow
May Harvest
June Harvest
July Harvest
August Fall Sowing
September Fall Sowing
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

50โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

204 days in Arlington County

Growing Tips for Borage in Arlington County

Direct sow Borage outdoors after April 10 in Arlington County when soil has warmed and frost danger has passed.

General growing tips

Direct sow in spring as borage does not transplant well. Allow some plants to go to seed for next year. Young leaves are best; older leaves become bristly.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Borage in Arlington County, VA?

Arlington County is in Zone 7a with an average last frost of April 10. Plan your Borage planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Arlington County, VA?

Arlington County, Virginia is in USDA Hardiness Zone 7a. The average last spring frost is April 10 and first fall frost is October 31.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Arlington 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 Arlington County, VA. Local conditions may vary. Last updated: April 2026.