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When to plant Vinca (Annual) in Compton, CA

Compton's 232-day season only supports one Vinca (Annual) planting per year. Sow between February 13 and February 27 for the best chance at full maturity before November 21.

When to Plant Vinca (Annual) in Compton, CA

Los Angeles County, California Zone 10b July

What to do in July

We've pulled the most time-sensitive tasks for Los Angeles County, California this July and put them front and centre. Tackle them in order.

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. Bring in the vinca (annual)

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

A few tasks this July that'll pay off in August
  • First harvests: vinca (annual)

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Annual vinca (Catharanthus roseus), also called Madagascar periwinkle, is one of the most heat- and drought-tolerant bedding plants available. Glossy foliage stays attractive all season while cheerful pinwheel blooms continue without deadheading. A top performer in hot, humid Southern summers where impatiens and begonias struggle. Self-cleaning; requires little maintenance once established.

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 Vinca (Annual) during the growing season. With low rainfall, drip irrigation is essential for growing Vinca (Annual) successfully. Mulch heavily to conserve soil moisture.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant
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

Vinca (Annual) Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Dec 26 Transplant: Jan 16 🌸 Bloom: Mar 27 – Nov 20
Recommended (50%) ✗ May not fit
Start indoors: Jan 23 Transplant: Feb 13 🌸 Bloom: Apr 24 – Dec 18
Safe Start (90%) ✓ Fits season (302 days to spare)
Start indoors: Mar 19 Transplant: Apr 9 🌸 Bloom: Jun 18 – Feb 11

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 Vinca (Annual)'s growing requirements.

Soil pH

Your soil pH (5.8–7.5) overlaps with Vinca (Annual)'s range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

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

How to Plant Vinca (Annual)

0.1"
Planting Depth
10"
Between Plants
12"
Between Rows

Succession Planting Vinca (Annual)

3
successive plantings in your 232-day season

Sow every 8 weeks. Last sowing by Aug 23 to harvest before frost.

Vinca (Annual) Water Budget

Plant needs
0.5″/week
Rainfall provides
0.2″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 660 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Vinca (Annual)

Vinca (Annual) needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Vinca (Annual) Needs Rainfall You Supplement Action
Jan 2.4" 0" ❄️ Dormant
Feb 2.5" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 2.2" 1.2" 1" 💧 Light watering
May 2.2" 0.4" 1.8" 🚿 Regular watering
Jun 2.2" 0.1" 2.1" 🚿 Regular watering
Jul 2.2" 0" 2.2" 🚿 Regular watering
Aug 2.2" 0" 2.2" 🚿 Regular watering
Sep 2.2" 0.2" 2" 🚿 Regular watering
Oct 2.2" 0.6" 1.6" 🚿 Regular watering
Nov 2.2" 1.3" 0.9" 💧 Light 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.

Vinca (Annual) 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.

Vinca (Annual) needs ~1,220 GDD — county provides 3,538 GDD Excellent fit

Vinca (Annual) Planting Timeline — Compton, CA

Vinca (Annual) Planting Calendar

Activity When Date Range
Start Indoors January 23 Jan 23 – Feb 6
Transplant Outdoors February 13 Feb 13 – Feb 27
Bloom April 24 Apr 24 – Dec 18

Plant 0.1" deep · 10" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · 1-2 times/week

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 10b

📆 Growing Season

232 days in Los Angeles County

Growing Tips for Vinca (Annual) in Compton

Direct sow Vinca (Annual) 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. Vinca (Annual) needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start seeds indoors 10–12 weeks before last frost — germination requires warm soil (75–80°F) and darkness. Do not cover seeds deeply; they need just a light dusting. Direct sowing is rarely practiced due to slow seedling establishment. Transplant after soil warms and frost danger has passed. Excellent drought tolerance once established; avoid overwatering. Performs best in well-drained beds or containers in full sun.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

When should I plant Vinca (Annual) in Compton, CA?

In Compton, CA, plant Vinca (Annual) 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 Vinca (Annual)?

Compton sits in USDA Zone 10b. Vinca (Annual) grows reliably in zones 3a through 11b, so it's a good fit here.

Can Vinca (Annual) grow in Compton's climate?

Yes — Vinca (Annual) 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.