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When to Plant Kiwi in Riverside County, CA

Kiwi vines produce fuzzy, tangy-sweet fruits and need both male and female plants for pollination. Hardy kiwi varieties (A. arguta) are suited to colder climates.

Riverside County, California is in USDA Zone 9b. The average last spring frost is February 24 and the first fall frost is December 4, giving you a growing season of approximately 283 days.

At an elevation of 1,206 feet, Riverside County receives approximately 15.5 inches of rainfall annually with predominantly loam soil. Summer highs average 102ยฐF, so Kiwi may need afternoon shade and extra watering during peak heat. With low rainfall, drip irrigation is essential for growing Kiwi successfully. Mulch heavily to conserve soil moisture.

Riverside County, CA (Zone 9b) Year-round
283 days
Last Spring Frost February 24
283 growing days
First Fall Frost December 4

Riverside County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Feb 17
Recommended (50%) ✓ Fits season
Transplant: Mar 10
Safe Start (90%) ✓ Fits season
Transplant: Apr 5

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 Riverside County

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

Soil pH

Your soil pH (6.2โ€“7.8) overlaps with Kiwi's range (5.5โ€“7.0), though not a perfect match.

Soil Texture

The loam soil in Riverside County is excellent for Kiwi โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.5%). Annual compost additions will help Kiwi.

How to Plant Kiwi

72"
Between Plants
96"
Between Rows

Plant 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 2,338 gal / 100 sq ft
Drought risk

Water stress score is 10/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Kiwi

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

Month Kiwi Needs Rainfall You Supplement Action
Jan โ€” 3.5" 0" โ„๏ธ Dormant
Feb 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Mar 4.3" 2.2" 2.1" ๐Ÿ’ง Light watering
Apr 4.3" 1.2" 3.1" ๐Ÿšฟ Regular watering
May 4.3" 0.4" 3.9" ๐Ÿšฟ Regular watering
Jun 4.3" 0.1" 4.2" ๐Ÿšฟ Regular watering
Jul 4.3" 0" 4.3" ๐Ÿšฟ Regular watering
Aug 4.3" 0" 4.3" ๐Ÿšฟ Regular watering
Sep 4.3" 0.2" 4.1" ๐Ÿšฟ Regular watering
Oct 4.3" 0.6" 3.7" ๐Ÿšฟ Regular watering
Nov 4.3" 1.5" 2.8" ๐Ÿšฟ Regular watering
Dec 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering

Water needs are for active growing months only (Febโ€“Dec in Riverside County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Kiwi 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" โ€” every day above 50ยฐF 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.

Kiwi needs ~38,690 GDD — county provides 7,526 GDD May not mature

Kiwi Planting Timeline โ€” Riverside County, CA

Kiwi Planting Calendar

Activity When Date Range
Transplant Outdoors March 10 Mar 10 โ€“ Mar 24

ยท 72" apart ยท Rows 96" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Transplant Outdoors
April โ€”
May โ€”
June โ€”
July โ€”
August โ€”
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

1095โ€“1825 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 9b

๐Ÿ“† Growing Season

283 days in Riverside County

Growing Tips for Kiwi in Riverside County

Direct sow Kiwi outdoors after February 24 in Riverside County when soil has warmed and frost danger has passed.

With summer highs reaching 102ยฐF in Riverside County, provide afternoon shade for Kiwi and water deeply in the morning.

Your 284.0-day growing season in Riverside County is tight for Kiwi (1095.0-1825.0 days to maturity). Start indoors and choose early-maturing varieties.

Riverside County receives only 16" of rain annually. Kiwi needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Plant one male vine for every 6-8 female vines. Provide a very sturdy arbor or T-bar trellis. Prune heavily in winter. Protect young plants from frost in cold zones.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Kiwi in Riverside County, CA?

Riverside County is in Zone 9b with an average last frost of February 24. Plan your Kiwi planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Riverside County, CA?

Riverside County, California is in USDA Hardiness Zone 9b. The average last spring frost is February 24 and first fall frost is December 4.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Riverside County gardeners in Zone 9b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Riverside County, CA. Local conditions may vary. Last updated: April 2026.