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When to plant Geraniums in Rockcastle County, KY

Plant Geraniums in Rockcastle County, between April 16 and April 30 — the only viable window. Zone 7a's short season (190 frost-free days) rules out a fall crop.

When to Plant Geraniums in Rockcastle County, KY

Rockcastle County, Kentucky Zone 7a August

This month in Rockcastle County, Kentucky

August is a pivotal month for Rockcastle County, Kentucky gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost April 16
Avg. first frost October 23
Soil temp (4") 79°F
Watering Low
Pest pressure High
Daylight 13.4 hrs
  1. Collect geraniums at their peak

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

September prep starts now
  • First harvests: geraniums

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Geraniums (Pelargonium × hortorum) are tender perennials grown as warm-season annuals throughout North America. Prized for their bold flower clusters, long bloom period, and tolerance of summer heat when planted in well-drained soil, they anchor window boxes, containers, and bed borders from late spring until hard frost. Zones 9b–11b can overwinter plants in the ground.

Rockcastle County, Kentucky is in USDA Zone 7a. The average last spring frost is April 16 and the first fall frost is October 23, giving you a growing season of approximately 190 days.

At an elevation of 1,677 feet, Rockcastle County receives approximately 41.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Geraniums during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Rockcastle County, KY (Zone 7a) Moderate season
190 days
Last Spring Frost April 16
190 growing days
First Fall Frost October 23

Rockcastle County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.9

Drainage

Well Drained

Geraniums Planting Risk Windows

Early Start (70% safe) ✓ Fits season (11 days to spare)
Start indoors: Jan 28 Transplant: Apr 8 🌸 Bloom: Jun 17 – Oct 7
Recommended (50%) ✓ Fits season (8 days to spare)
Start indoors: Feb 5 Transplant: Apr 16 🌸 Bloom: Jun 25 – Oct 15
Safe Start (90%) ✓ Fits season (3 days to spare)
Start indoors: Feb 20 Transplant: May 1 🌸 Bloom: Jul 10 – Oct 30

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 Rockcastle County

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

Soil pH

Your soil pH (5.3–6.9) overlaps with Geraniums's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

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

How to Plant Geraniums

0.1"
Planting Depth
12"
Between Plants
14"
Between Rows

Succession Planting Geraniums

3
successive plantings in your 190-day season

Sow every 8 weeks. Last sowing by Jul 15 to harvest before frost.

Geraniums Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 143 gal / 100 sq ft

Monthly Watering Guide for Geraniums

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

Month Geraniums Needs Rainfall You Supplement Action
Jan 3.1" 0" ❄️ Dormant
Feb 3.6" 0" ❄️ Dormant
Mar 4.1" 0" ❄️ Dormant
Apr 4.3" 3.4" 0.9" 💧 Light watering
May 4.3" 3" 1.3" 💧 Light watering
Jun 4.3" 3.5" 0.8" 💧 Light watering
Jul 4.3" 3.9" 0.4" 💧 Light watering
Aug 4.3" 3.8" 0.5" 💧 Light watering
Sep 4.3" 3.2" 1.1" 💧 Light watering
Oct 4.3" 3.1" 1.2" 💧 Light watering
Nov 3.3" 0" ❄️ Dormant
Dec 3.3" 0" ❄️ Dormant

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

Geraniums 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.

Geraniums needs ~1,551 GDD — county provides 3,467 GDD Excellent fit

Geraniums Planting Timeline — Rockcastle County, KY

Geraniums Planting Calendar

Activity When Date Range
Start Indoors February 5 Feb 5 – Feb 19
Transplant Outdoors April 16 Apr 16 – Apr 30
Bloom June 25 Jun 25 – Oct 15

Plant 0.1" deep · 12" apart · Rows 14" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

190 days in Rockcastle County

Growing Tips for Geraniums in Rockcastle County

Direct sow Geraniums outdoors after April 16 in Rockcastle County when soil has warmed and frost danger has passed.

General growing tips

Start seeds indoors 10–12 weeks before last frost — germination is slow and erratic without bottom heat (70–75°F). Transplant after frost danger passes. Geraniums rarely direct-sown; cuttings or transplants are the standard. Deadhead spent umbels weekly to maintain continuous bloom. Let soil dry slightly between waterings to prevent root rot. In zones 10–11 plants may be left in ground year-round or overwintered as houseplants.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Geraniums in Rockcastle County, KY?

Rockcastle County is in Zone 7a with an average last frost of April 16. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.

What planting zone is Rockcastle County, KY?

Rockcastle County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 16 and first fall frost is October 23.

When should I plant Geraniums in Rockcastle County, KY?

In Rockcastle County, KY, plant Geraniums after the last frost (around April 16) and before the first frost (around October 23). Best results when soil holds above 50°F.

What growing zone is Rockcastle County, KY for Geraniums?

Rockcastle County sits in USDA Zone 7a. Geraniums grows reliably in zones 2a through 11b, so it's a good fit here.

Can Geraniums grow in Rockcastle County's climate?

Yes — Geraniums grows well in Rockcastle County's temperate climate. Rockcastle County averages a 190-day frost-free season, with last frost around April 16 and first frost around October 23.

🌱

Your Rockcastle County Garden Planner — Free

A 22-page printable planner built for Rockcastle 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 Rockcastle County, KY. Local conditions may vary. Last updated: August 2026.

Sources & credits

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