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When to plant Gladiolus in Compton, CA

In Compton, plant Gladiolus in spring between April 3 and April 24, once soil temps hold above 50°F. Compton's last frost averages April 3, so aim for a steady week of warm soil before planting. For a fall crop, sow between and — roughly 70–100 days before the first frost on November 21.

When to Plant Gladiolus in Compton, CA

Los Angeles County, California Zone 10b July

July to-do list for Los Angeles County, California

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Avg. last frost April 3
Avg. first frost November 21
Soil temp (4") 93°F
Watering Critical
Pest pressure High
Daylight 14.1 hrs
  1. Pick gladiolus

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

Before August arrives, get these ready
  • 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.

Compton, California is in USDA Zone 10b. The average last spring frost is April 3 and the first fall frost is November 21, giving you a growing season of approximately 232 days.

At an elevation of 1,315 feet, Los Angeles County receives approximately 12.9 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Gladiolus during the growing season. With low rainfall, drip irrigation is essential for growing Gladiolus successfully. Mulch heavily to conserve soil moisture.

Bulb Blooms in Summer Pollinator-friendly Good for cutting
Compton, CA (Zone 10b) Long season
232 days
Last Spring Frost April 3
232 growing days
First Fall Frost November 21

Compton Soil Profile

Soil Type

Loam

Soil pH

5.8-7.5

Drainage

Well Drained

Gladiolus Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Mar 6 🌸 Bloom: May 15 – Dec 25
Recommended (50%) ✓ Fits season (303 days to spare)
Transplant: Apr 3 🌸 Bloom: Jun 12 – Jan 22
Safe Start (90%) ✓ Fits season (267 days to spare)
Transplant: May 28 🌸 Bloom: Aug 6 – Mar 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 Compton

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

Soil pH

Your soil pH (5.8–7.5) is more alkaline than Gladiolus prefers (6.0–6.5). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.1%). Annual compost additions will help Gladiolus.

How to Plant Gladiolus

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

Succession Planting Gladiolus

3
successive plantings in your 232-day season

Sow every 8 weeks. Last sowing by Aug 13 to harvest before frost.

Gladiolus Water Budget

Plant needs
1.0″/week
Rainfall provides
0.2″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 1,899 gal / 100 sq ft
Drought risk

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

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 2.4" 0" ❄️ Dormant
Feb 2.5" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 4.3" 1.2" 3.1" 🚿 Regular watering
May 4.3" 0.4" 3.9" 🚿 Regular watering
Jun 4.3" 0.1" 4.2" 🚿 Regular watering
Jul 4.3" 0" 4.3" 🚿 Regular watering
Aug 4.3" 0" 4.3" 🚿 Regular watering
Sep 4.3" 0.2" 4.1" 🚿 Regular watering
Oct 4.3" 0.6" 3.7" 🚿 Regular watering
Nov 4.3" 1.3" 3" 🚿 Regular watering
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Nov in Los Angeles 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 3,538 GDD Excellent fit

Gladiolus Planting Timeline — Compton, CA

Gladiolus Planting Calendar

Activity When Date Range
Transplant Outdoors April 3 Apr 3 – Apr 17
Direct Sow April 3 Apr 3 – Apr 24
Bloom June 12 Jun 12 – Jan 22

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 2-3 times/week

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–6.5 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 10b

📆 Growing Season

232 days in Los Angeles County

Growing Tips for Gladiolus in Compton

Direct sow Gladiolus outdoors after April 03 in Los Angeles County when soil has warmed and frost danger has passed.

Los Angeles County receives only 13" of rain annually. Gladiolus needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

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 →

When should I plant Gladiolus in Compton, CA?

In Compton, CA, plant Gladiolus after the last frost (around April 3) and before the first frost (around November 21). Best results when soil holds above 50°F.

What growing zone is Compton, CA for Gladiolus?

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

Can Gladiolus grow in Compton's climate?

Yes — Gladiolus grows well in Compton's temperate climate. Compton averages a 232-day frost-free season, with last frost around April 3 and first frost around November 21.

🌱

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A 22-page printable planner built for Los Angeles County (Zone 10b). 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 Los Angeles County, CA. Local conditions may vary. Last updated: July 2026.