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When to plant Begonias in Lake County County,

Plant Begonias in Lake County County during the brief April 28–May 12 window. With 182 frost-free days, fall plantings can't mature before October 20.

When to Plant Begonias in Lake County, IL

Lake County, Illinois Zone 6a June

June in Lake County, Illinois — your action list

Your Lake County, Illinois garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.

Avg. last frost April 21
Avg. first frost October 20
Soil temp (4") 70°F
Watering Low
Pest pressure High
Daylight 15.1 hrs
  1. Start begonias under lights

    These need a head start before your last frost (April 21). Sow into cells now so you're ready to transplant in a few weeks.

Coming up in July — start thinking about
  • First harvests: begonias

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Wax begonias (Begonia × semperflorens) are the workhorse shade bedding plant of American horticulture, offering continuous bloom from transplant to hard frost. Bronze or green-leaved varieties perform well from deep shade to full sun (in northern zones) and tolerate summer humidity better than most cool- season flowers. A staple of mass plantings, containers, and window boxes.

Lake County, Illinois is in USDA Zone 6a. The average last spring frost is April 21 and the first fall frost is October 20, giving you a growing season of approximately 182 days.

At an elevation of 1,080 feet, Lake County receives approximately 33.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Begonias to ensure they mature before fall.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant
Lake County, IL (Zone 6a) Moderate season
182 days
Last Spring Frost April 21
182 growing days
First Fall Frost October 20
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Lake County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-6.9

Drainage

Well Drained

Begonias Planting Risk Windows

Early Start (70% safe) ✓ Fits season (10 days to spare)
Start indoors: Feb 5 Transplant: Apr 23 🌸 Bloom: Jul 2 – Oct 1
Recommended (50%) ✓ Fits season (14 days to spare)
Start indoors: Feb 10 Transplant: Apr 28 🌸 Bloom: Jul 7 – Oct 6
Safe Start (90%) ✓ Fits season (12 days to spare)
Start indoors: Feb 28 Transplant: May 16 🌸 Bloom: Jul 25 – Oct 24

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 Lake County

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

Soil pH

Your soil pH (6.2–6.9) is more alkaline than Begonias prefers (5.5–6.5). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.9%). Annual compost additions will help Begonias.

How to Plant Begonias

8"
Between Plants
10"
Between Rows

Succession Planting Begonias

3
successive plantings in your 182-day season

Sow every 8 weeks. Last sowing by Jul 22 to harvest before frost.

Begonias Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 441 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Begonias

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

Month Begonias Needs Rainfall You Supplement Action
Jan 1.5" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2" 0" ❄️ Dormant
Apr 4.3" 3.3" 1" 💧 Light watering
May 4.3" 3.9" 0.4" 💧 Light watering
Jun 4.3" 4.4" 0" ✅ Rainfall sufficient
Jul 4.3" 3.3" 1" 💧 Light watering
Aug 4.3" 3.4" 0.9" 💧 Light watering
Sep 4.3" 3.3" 1" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 2.3" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

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

Begonias 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.

Begonias needs ~980 GDD — county provides 2,229 GDD Excellent fit

Begonias Planting Timeline — Lake County, IL

Begonias Planting Calendar

Activity When Date Range
Start Indoors February 10 Feb 10 – Feb 24
Transplant Outdoors April 28 Apr 28 – May 12
Bloom July 7 Jul 7 – Oct 6

· 8" apart · Rows 10" apart

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 5.5–6.5 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 6a

📆 Growing Season

182 days in Lake County

Growing Tips for Begonias in Lake County

Direct sow Begonias outdoors after April 21 in Lake 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; surface-sow on moist mix under lights, do not cover. Bottom heat (70–75°F) speeds germination. Transplant after frost; begonias are not direct-sown in practice. Pinch seedlings once for branching. Keep soil evenly moist; avoid waterlogged conditions. Bronze-leaf types tolerate more sun; green- leaf types prefer shade to part-sun.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Begonias in Lake County, IL?

Lake County is in Zone 6a with an average last frost of April 21. Plan your Begonias planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lake County, IL?

Lake County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 21 and first fall frost is October 20.

When should I plant Begonias in Lake County County, ?

In Lake County County, , plant Begonias after the last frost (around April 21) and before the first frost (around October 20). Best results when soil holds above 50°F.

What growing zone is Lake County County, for Begonias?

Lake County County sits in USDA Zone 6a. Begonias grows reliably in zones 2a through 11b, so it's a good fit here.

Can Begonias grow in Lake County County's climate?

Yes — Begonias grows well in Lake County County's temperate climate. Lake County County averages a 182-day frost-free season, with last frost around April 21 and first frost around October 20.

🌱

Your Lake County Garden Planner — Free

A 22-page printable planner built for Lake County (Zone 6a). 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 Lake County, IL. 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.