Blog

When to plant Hydrangeas in Lyon County County,

In Lyon County County, Hydrangeas is a spring-only crop. Plant April 11–April 25 once soil hits 50°F.

When to Plant Hydrangeas in Lyon County, KY

Lyon County, Kentucky Zone 7a June

Top priorities for Lyon County, Kentucky gardeners in June

Each item below is timed to Lyon County, Kentucky's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 4
Avg. first frost November 1
Soil temp (4") 66°F
Watering Low
Pest pressure High
Daylight 14.5 hrs
  1. Time to start hydrangeas inside

    Label every cell. You will absolutely forget which is which otherwise.

  2. Bring in the hydrangeas

    If you can't use it all right away, check the food-preservation section of your planner.

July prep starts now
  • First harvests: hydrangeas

Instant PDF download. No spam, unsubscribe any time.

Hydrangeas (Hydrangea spp.) are among the most spectacular summer-blooming shrubs, with large mophead, lacecap, or panicle flower clusters lasting weeks in the garden and drying beautifully for arrangements. Native to Asia and North America alike, the genus spans several garden species with different hardiness and blooming habits. Panicle hydrangeas (H. paniculata, e.g., Limelight) are the most cold-hardy (Zone 3) and most reliable bloomers; smooth hydrangeas (H. arborescens, e.g., Annabelle) are equally tough. Bigleaf hydrangeas (H. macrophylla) are prized for blue/pink color-shifting blooms but require reliable snow cover or winter protection in Zones 5–6. Flower color in macrophylla types is determined by soil pH (acidic = blue, alkaline = pink).

Lyon County, Kentucky is in USDA Zone 7a. The average last spring frost is April 4 and the first fall frost is November 1, giving you a growing season of approximately 211 days.

At an elevation of 2,809 feet, Lyon County receives approximately 46.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Hydrangeas during the growing season.

Perennial Blooms in Summer Pollinator-friendly Good for cutting
Lyon County, KY (Zone 7a) Long season
211 days
Last Spring Frost April 4
211 growing days
First Fall Frost November 1
Share this guide:

Lyon County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.6

Drainage

Well Drained

Hydrangeas Planting Risk Windows

Early Start (70% safe) ✓ Fits season (26 days to spare)
Start indoors: Jan 15 Transplant: Apr 2 🌸 Bloom: Jun 11 – Oct 1
Recommended (50%) ✓ Fits season (22 days to spare)
Start indoors: Jan 24 Transplant: Apr 11 🌸 Bloom: Jun 20 – Oct 10
Safe Start (90%) ✓ Fits season (29 days to spare)
Start indoors: Feb 6 Transplant: Apr 24 🌸 Bloom: Jul 3 – Oct 23

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 Lyon County

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

Soil pH

Your soil pH (5.7–6.6) overlaps with Hydrangeas's range (5.5–6.5), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Hydrangeas.

Organic Matter

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

How to Plant Hydrangeas

1"
Planting Depth
48"
Between Plants
60"
Between Rows

Hydrangeas Water Budget

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

Monthly Watering Guide for Hydrangeas

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

Month Hydrangeas Needs Rainfall You Supplement Action
Jan 4.3" 0" ❄️ Dormant
Feb 3.6" 0" ❄️ Dormant
Mar 4.7" 0" ❄️ Dormant
Apr 4.3" 4" 0.3" 💧 Light watering
May 4.3" 3.7" 0.6" 💧 Light watering
Jun 4.3" 3.8" 0.5" 💧 Light watering
Jul 4.3" 5.5" 0" ✅ Rainfall sufficient
Aug 4.3" 4" 0.3" 💧 Light watering
Sep 4.3" 3.8" 0.5" 💧 Light watering
Oct 4.3" 2.5" 1.8" 💧 Light watering
Nov 4.3" 3.4" 0.9" 💧 Light watering
Dec 3.4" 0" ❄️ Dormant

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

Hydrangeas 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.

Hydrangeas needs ~1,650 GDD — county provides 2,901 GDD Excellent fit

Hydrangeas Planting Timeline — Lyon County, KY

Hydrangeas Planting Calendar

Activity When Date Range
Start Indoors January 24 Jan 24 – Feb 7
Transplant Outdoors April 11 Apr 11 – Apr 25
Bloom June 20 Jun 20 – Oct 10

Plant 1" deep · 48" apart · Rows 60" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Start Indoors
March
April Transplant Outdoors
May
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November
December
Share this guide:

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

90–150 days

🧪 Soil pH

Needs 5.5–6.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

211 days in Lyon County

Growing Tips for Hydrangeas in Lyon County

Direct sow Hydrangeas outdoors after April 04 in Lyon County when soil has warmed and frost danger has passed.

General growing tips

Plant container-grown specimens in spring or fall, spacing at least 3–5 feet apart to allow for mature shrub spread. Most hydrangeas prefer morning sun with afternoon shade, especially in Zones 7+. Keep consistently moist — the name derives from the Greek for water vessel. Prune panicle and smooth types in late winter/early spring (they bloom on new wood). Prune bigleaf types only lightly after bloom; cutting stems in fall removes next year's buds. In Zone 5–6, protect bigleaf varieties with burlap or wire cages filled with leaves over winter. Fall planting (Zones 5+) gives excellent root establishment before summer heat. Year 2+ plants reach full size and bloom.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Hydrangeas in Lyon County, KY?

Lyon County is in Zone 7a with an average last frost of April 4. Plan your Hydrangeas planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lyon County, KY?

Lyon County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 4 and first fall frost is November 1.

When should I plant Hydrangeas in Lyon County County, ?

In Lyon County County, , plant Hydrangeas after the last frost (around April 4) and before the first frost (around November 1). Best results when soil holds above 50°F.

What growing zone is Lyon County County, for Hydrangeas?

Lyon County County sits in USDA Zone 7a. Hydrangeas grows reliably in zones 3a through 9a, so it's a good fit here.

Can Hydrangeas grow in Lyon County County's climate?

Yes — Hydrangeas grows well in Lyon County County's temperate climate. Lyon County County averages a 211-day frost-free season, with last frost around April 4 and first frost around November 1.

🌱

Your Lyon County Garden Planner — Free

A 22-page printable planner built for Lyon 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.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Lyon County, KY. 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.