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When to Plant Nasturtium in Loudoun County, VA

Loudoun County, Virginia Zone 7a June

Top priorities for Loudoun County, Virginia gardeners in June

Here's what deserves your attention in Loudoun County, Virginia this month. Everything below is tailored to Zone 7a and timed around your local frost dates.

Avg. last frost April 18
Avg. first frost October 19
Soil temp (4") 79°F
Watering Low
Pest pressure High
Daylight 14.7 hrs
  1. Harvest nasturtium as they ripen

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

Get ahead of July
  • First harvests: nasturtium

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Nasturtium (Tropaeolum majus) is a fast-growing annual with distinctive round, lily-pad leaves and bold trumpet-shaped blooms in warm oranges, reds, and yellows. Both the flowers and leaves are edible with a peppery watercress flavor. Planted near vegetables, nasturtiums act as a sacrifice trap-crop, luring aphids away from more valuable plants. They thrive in poor, dry soil — rich conditions produce lush foliage but few flowers.

Loudoun County, Virginia 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 857 feet, Loudoun County receives approximately 45.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 94°F, providing good warmth for Nasturtium during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Loudoun County, VA (Zone 7a) Moderate season
184 days
Last Spring Frost April 18
184 growing days
First Fall Frost October 19
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Loudoun County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.5

Drainage

Well Drained

Nasturtium Planting Risk Windows

Early Start (70% safe) ✓ Fits season (4 days to spare)
Start indoors: Mar 16 Transplant: Apr 13 🌸 Bloom: Jun 8 – Oct 12
Recommended (50%) ✓ Fits season (2 days to spare)
Start indoors: Mar 21 Transplant: Apr 18 🌸 Bloom: Jun 13 – Oct 17
Safe Start (90%) ✗ May not fit
Start indoors: Apr 12 Transplant: May 10 🌸 Bloom: Jul 5 – Nov 8

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 Loudoun County

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

Soil pH

Your soil pH (5.3–6.5) is more acidic than Nasturtium prefers (6.0–8.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Loudoun County is excellent for Nasturtium — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Nasturtium prefers dry conditions but your soil drains poorly. Use raised beds or mounded rows to prevent root rot.

Organic Matter

Organic matter is moderate (2.8%). Annual compost additions will help Nasturtium.

How to Plant Nasturtium

0.5"
Planting Depth
10"
Between Plants
12"
Between Rows

Succession Planting Nasturtium

3
successive plantings in your 184-day season

Sow every 6.3 weeks. Last sowing by Aug 15 to harvest before frost.

Nasturtium Water Budget

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

Monthly Watering Guide for Nasturtium

Nasturtium 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 Nasturtium Needs Rainfall You Supplement Action
Jan 3.5" 0" ❄️ Dormant
Feb 3.4" 0" ❄️ Dormant
Mar 4" 0" ❄️ Dormant
Apr 2.2" 4" 0" ✅ Rainfall sufficient
May 2.2" 3.2" 0" ✅ Rainfall sufficient
Jun 2.2" 4.7" 0" ✅ Rainfall sufficient
Jul 2.2" 4.4" 0" ✅ Rainfall sufficient
Aug 2.2" 4.6" 0" ✅ Rainfall sufficient
Sep 2.2" 3.3" 0" ✅ Rainfall sufficient
Oct 2.2" 3.4" 0" ✅ Rainfall sufficient
Nov 3.5" 0" ❄️ Dormant
Dec 3.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Loudoun County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Nasturtium 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.

Nasturtium needs ~1,230 GDD — county provides 3,772 GDD Excellent fit

Nasturtium Planting Timeline — Loudoun County, VA

Nasturtium Planting Calendar

Activity When Date Range
Start Indoors March 21 Mar 21 – Apr 4
Transplant Outdoors April 18 Apr 18 – May 2
Direct Sow April 18 Apr 18 – May 9
Bloom June 13 Jun 13 – Oct 17

Plant 0.5" deep · 10" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

55–65 days

🧪 Soil pH

Needs 6–8 · Your soil: too_acidic

🗺️ USDA Zone

Zone 7a

📆 Growing Season

184 days in Loudoun County

Growing Tips for Nasturtium in Loudoun County

Direct sow Nasturtium outdoors after April 18 in Loudoun County when soil has warmed and frost danger has passed.

General growing tips

Direct-sow large seeds 1/2 inch deep after last frost; soak seeds overnight to speed germination (7-10 days). Nasturtiums dislike root disturbance so direct sowing is strongly preferred. Avoid fertilizing — poor soil brings the best bloom. Trailing types can cover banks and climb trellises; dwarf types suit containers. In hot climates (zones 9+) plant in fall for winter/spring bloom as plants struggle in peak summer heat.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Nasturtium in Loudoun County, VA?

Loudoun County is in Zone 7a with an average last frost of April 18. Plan your Nasturtium planting based on this frost date — see the calendar above for exact timing.

What planting zone is Loudoun County, VA?

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

🌱

Your Loudoun County Garden Planner — Free

A 22-page printable planner built for Loudoun County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.