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When to Plant Lobelia in Sussex County, VA

Sussex County, Virginia Zone 7b June

June to-do list for Sussex County, Virginia

If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.

Avg. last frost March 28
Avg. first frost November 7
Soil temp (4") 79°F
Watering Low
Pest pressure High
Daylight 14.5 hrs
  1. Harvest lobelia as they ripen

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

July prep starts now
  • First harvests: lobelia

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Lobelia (Lobelia erinus) is a cool-season annual prized for the intense cobalt blue that is rare among bedding flowers. It blooms most prolifically in spring and early summer but stalls or dies back during heat peaks above 90°F. In zones 3–7 it delivers a long display; in zones 8–9 it is best treated as a spring annual that fades by midsummer. Trailing types cascade beautifully from containers and window boxes.

Sussex County, Virginia is in USDA Zone 7b. The average last spring frost is March 28 and the first fall frost is November 7, giving you a growing season of approximately 224 days.

At an elevation of 1,076 feet, Sussex County receives approximately 41.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Lobelia during the growing season.

Annual Blooms in Spring Pollinator-friendly
Sussex County, VA (Zone 7b) Long season
224 days
Last Spring Frost March 28
224 growing days
First Fall Frost November 7
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Sussex County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.9

Drainage

Well Drained

Lobelia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (128 days to spare)
Start indoors: Jan 18 Transplant: Feb 22 🌸 Bloom: Apr 19 – Jun 28
Recommended (50%) ✓ Fits season (126 days to spare)
Start indoors: Jan 24 Transplant: Feb 28 🌸 Bloom: Apr 25 – Jul 4
Safe Start (90%) ✓ Fits season (124 days to spare)
Start indoors: Feb 7 Transplant: Mar 14 🌸 Bloom: May 9 – Jul 18

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 Sussex County

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

Soil pH

Your soil pH (5.7–6.9) overlaps with Lobelia's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.4%). Annual compost additions will help Lobelia.

How to Plant Lobelia

6"
Between Plants
8"
Between Rows

Succession Planting Lobelia

3
successive plantings in your 224-day season

Sow every 8 weeks. Last sowing by Aug 19 to harvest before frost.

Lobelia Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 442 gal / 100 sq ft

Monthly Watering Guide for Lobelia

Lobelia needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Lobelia Needs Rainfall You Supplement Action
Jan 3.7" 0" ❄️ Dormant
Feb 3.6" 0" ❄️ Dormant
Mar 4.3" 3.8" 0.5" 💧 Light watering
Apr 4.3" 2.8" 1.5" 💧 Light watering
May 4.3" 3.3" 1" 💧 Light watering
Jun 4.3" 3.8" 0.5" 💧 Light watering
Jul 4.3" 4" 0.3" 💧 Light watering
Aug 4.3" 4.1" 0.2" 💧 Light watering
Sep 4.3" 3.4" 0.9" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 4.3" 3.4" 0.9" 💧 Light watering
Dec 2.7" 0" ❄️ Dormant

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

Lobelia 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.

Lobelia needs ~1,312 GDD — county provides 3,920 GDD Excellent fit

Lobelia Planting Timeline — Sussex County, VA

Lobelia Planting Calendar

Activity When Date Range
Start Indoors January 24 Jan 24 – Feb 7
Transplant Outdoors February 28 Feb 28 – Mar 14
Bloom April 25 Apr 25 – Jul 4

· 6" apart · Rows 8" apart

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

70–80 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7b

📆 Growing Season

224 days in Sussex County

Growing Tips for Lobelia in Sussex County

Direct sow Lobelia outdoors after March 28 in Sussex County when soil has warmed and frost danger has passed.

General growing tips

Start seeds indoors 10–12 weeks before last frost — seed is dust-fine and requires light to germinate; surface-sow and press gently. Keep at 65–70°F. Not reliably direct-sown. Transplant in cool weather, 2–4 weeks before last frost date is acceptable in zones 5+. Shear plants by one-third after the first bloom flush to encourage a second flush in fall. Provide afternoon shade in zones 7+ to extend bloom into summer.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Lobelia in Sussex County, VA?

Sussex County is in Zone 7b with an average last frost of March 28. Plan your Lobelia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sussex County, VA?

Sussex County, Virginia is in USDA Hardiness Zone 7b. The average last spring frost is March 28 and first fall frost is November 7.

🌱

Your Sussex County Garden Planner — Free

A 22-page printable planner built for Sussex County (Zone 7b). 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 Sussex 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.