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When to plant Gladiolus in Clark County County,

For Gladiolus in Clark County County, the safe spring window opens around April 10 and closes around May 1. Last expected frost is April 10, first fall frost October 22, giving a 195-day growing season.

When to Plant Gladiolus in Clark County, IN

Clark County, Indiana Zone 7a June

What to do in June

Your Clark County, Indiana 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 10
Avg. first frost October 22
Soil temp (4") 72°F
Watering Low
Pest pressure High
Daylight 14.7 hrs
  1. Bring in the gladiolus

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

A few tasks this June that'll pay off in July
  • First harvests: gladiolus

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Gladiolus (Gladiolus spp.) produce tall, stately spikes of trumpet-shaped blooms in a rich array of colors, making them one of the most popular cut flowers in the world. Each spike carries 12–20 florets that open in succession from bottom to top over 7–10 days. By planting corms every two weeks from last frost through early summer, gardeners create a continuous succession of fresh blooms from midsummer through fall. Corms multiply each season — a single planting becomes a growing collection over the years. Ideal for back-of- border planting, cutting gardens, and mixed summer containers.

Clark County, Indiana is in USDA Zone 7a. The average last spring frost is April 10 and the first fall frost is October 22, giving you a growing season of approximately 195 days.

At an elevation of 1,265 feet, Clark County receives approximately 36.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Gladiolus during the growing season.

Bulb Blooms in Summer Pollinator-friendly Good for cutting
Clark County, IN (Zone 7a) Moderate season
195 days
Last Spring Frost April 10
195 growing days
First Fall Frost October 22

Clark County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.7

Drainage

Well Drained

Gladiolus Planting Risk Windows

Early Start (70% safe) ✓ Fits season (0 days to spare)
Transplant: Apr 4 🌸 Bloom: Jun 13 – Oct 17
Recommended (50%) ✗ May not fit
Transplant: Apr 10 🌸 Bloom: Jun 19 – Oct 23
Safe Start (90%) ✗ May not fit
Transplant: Apr 30 🌸 Bloom: Jul 9 – Nov 12

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 Clark County

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

Soil pH

Your soil pH (5.8–6.7) overlaps with Gladiolus's range (6.0–6.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.3%) — Gladiolus will thrive.

How to Plant Gladiolus

5"
Planting Depth
5"
Between Plants
12"
Between Rows

Succession Planting Gladiolus

3
successive plantings in your 195-day season

Sow every 8 weeks. Last sowing by Jul 14 to harvest before frost.

Gladiolus 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 356 gal / 100 sq ft

Monthly Watering Guide for Gladiolus

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

Month Gladiolus Needs Rainfall You Supplement Action
Jan 1.4" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.9" 0" ❄️ Dormant
Apr 4.3" 3.8" 0.5" 💧 Light watering
May 4.3" 4.5" 0" ✅ Rainfall sufficient
Jun 4.3" 4.5" 0" ✅ Rainfall sufficient
Jul 4.3" 4.1" 0.2" 💧 Light watering
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 2.8" 1.5" 💧 Light watering
Oct 4.3" 3" 1.3" 💧 Light watering
Nov 3" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

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

Gladiolus 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.

Gladiolus needs ~1,296 GDD — county provides 2,973 GDD Excellent fit

Gladiolus Planting Timeline — Clark County, IN

Gladiolus Planting Calendar

Activity When Date Range
Transplant Outdoors April 10 Apr 10 – Apr 24
Direct Sow April 10 Apr 10 – May 1
Bloom June 19 Jun 19 – Oct 23

Plant 5" deep · 5" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Transplant Outdoors Direct Sow
May Direct Sow
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 6–6.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

195 days in Clark County

Growing Tips for Gladiolus in Clark County

Direct sow Gladiolus outdoors after April 10 in Clark County when soil has warmed and frost danger has passed.

General growing tips

Plant corms 4–6 inches deep, pointed end up, as soon as soil reaches 60°F after last frost. Space 4–6 inches apart; rows 12 inches apart. Stake or grow through a support grid — tall varieties reach 4–5 feet and tip in wind. Begin succession plantings every 2 weeks through early July for continuous bloom. Water deeply once a week; mulch to conserve moisture and suppress weeds. Cut spikes for vases when the lowest floret just begins to open. After first killing frost (in cold zones), dig corms, let dry for 3–4 weeks in a ventilated spot, remove cormels, and store in mesh bags at 35–50°F. In zones 7b–8a, corms sometimes survive mild winters in ground with heavy mulch; in zones 8b+, in-ground overwintering is reliable.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Gladiolus in Clark County, IN?

Clark County is in Zone 7a with an average last frost of April 10. Plan your Gladiolus planting based on this frost date — see the calendar above for exact timing.

What planting zone is Clark County, IN?

Clark County, Indiana is in USDA Hardiness Zone 7a. The average last spring frost is April 10 and first fall frost is October 22.

When should I plant Gladiolus in Clark County, ?

In Clark County, , plant Gladiolus after the last frost (around April 10) and before the first frost (around October 22). Best results when soil holds above 50°F.

What growing zone is Clark County, for Gladiolus?

Clark County sits in USDA Zone 7a. Gladiolus grows reliably in zones 3a through 10b, so it's a good fit here.

Can Gladiolus grow in Clark County's climate?

Yes — Gladiolus grows well in Clark County's temperate climate. Clark County averages a 195-day frost-free season, with last frost around April 10 and first frost around October 22.

🌱

Your Clark County Garden Planner — Free

A 22-page printable planner built for Clark 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 Clark County, IN. 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.