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When to Plant Escarole in Santa Clara County, CA

Santa Clara County, California Zone 9b May

Your May planting checklist for Santa Clara County, California

Welcome to May in Zone 9b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost February 19
Avg. first frost December 3
Soil temp (4") 74°F
Watering Critical
Pest pressure High
Daylight 14 hrs
  1. Basket week: escarole

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

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Escarole is a broad-leaved endive with slightly bitter, sturdy leaves. The outer leaves are more bitter while the blanched heart is tender and mild.

Santa Clara County, California is in USDA Zone 9b. The average last spring frost is February 19 and the first fall frost is December 3, giving you a growing season of approximately 287 days.

At an elevation of 455 feet, Santa Clara County receives approximately 15.5 inches of rainfall annually with predominantly loam soil. Summer highs average 92°F, providing good warmth for Escarole during the growing season. With low rainfall, drip irrigation is essential for growing Escarole successfully. Mulch heavily to conserve soil moisture.

Santa Clara County, CA (Zone 9b) Year-round
287 days
Last Spring Frost February 19
287 growing days
First Fall Frost December 3
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Santa Clara County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (211 days to spare)
Start indoors: Jan 4 Transplant: Feb 1 🍅 Harvest: Mar 29 – Apr 26
Recommended (50%) ✓ Fits season (203 days to spare)
Start indoors: Jan 22 Transplant: Feb 19 🍅 Harvest: Apr 16 – May 14
Safe Start (90%) ✓ Fits season (156 days to spare)
Start indoors: Mar 27 Transplant: Apr 24 🍅 Harvest: Jun 19 – Jul 17

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 Santa Clara County

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

Soil pH

Your soil pH (6.7–7.8) is more alkaline than Escarole prefers (5.5–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Santa Clara County is excellent for Escarole — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Escarole.

How to Plant Escarole

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Escarole

6
successive plantings in your 287-day season

Sow every 5.7 weeks. Last sowing by Sep 24 to harvest before frost.

For a dedicated fall crop, sow by Oct 08.

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 2,381 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Escarole

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

Month Escarole Needs Rainfall You Supplement Action
Jan 3.2" 0" ❄️ Dormant
Feb 4.3" 3.6" 0.7" 💧 Light watering
Mar 4.3" 2.6" 1.7" 💧 Light watering
Apr 4.3" 1.1" 3.2" 🚿 Regular watering
May 4.3" 0.3" 4" 🚿 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" 0.1" 4.2" 🚿 Regular watering
Oct 4.3" 0.6" 3.7" 🚿 Regular watering
Nov 4.3" 1.4" 2.9" 🚿 Regular watering
Dec 4.3" 2.6" 1.7" 💧 Light watering

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

Escarole 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.

Escarole needs ~1,140 GDD — county provides 5,472 GDD Excellent fit

Escarole Planting Timeline — Santa Clara County, CA

Escarole Planting Calendar

Activity When Date Range
Start Indoors January 22 Jan 22 – Feb 5
Transplant Outdoors February 19 Feb 19 – Mar 5
Direct Sow January 29 Jan 29 – Feb 19
Harvest April 16 Apr 16 – May 14
Fall Sowing October 8 Oct 8 – Oct 22

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors Direct Sow
February Start Indoors Transplant Outdoors Direct Sow
March Transplant Outdoors
April Harvest
May Harvest
June
July
August
September
October Fall Sowing
November
December
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Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · 2-3 times/week

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 9b

📆 Growing Season

287 days in Santa Clara County

Growing Tips for Escarole in Santa Clara County

Direct sow Escarole outdoors after February 19 in Santa Clara County when soil has warmed and frost danger has passed.

Common pests for Escarole in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

Santa Clara County receives only 16" of rain annually. Escarole needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow in spring or late summer. Blanch heads by tying outer leaves together or covering with a pot for 2 weeks before harvest. Excellent braised or in soups.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Escarole in Santa Clara County, CA?

Santa Clara County is in Zone 9b with an average last frost of February 19. Plan your Escarole planting based on this frost date — see the calendar above for exact timing.

What planting zone is Santa Clara County, CA?

Santa Clara County, California is in USDA Hardiness Zone 9b. The average last spring frost is February 19 and first fall frost is December 3.

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Your Santa Clara County Garden Planner — Free

A 24-page printable planner built for Santa Clara County (Zone 9b). 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 Santa Clara County, CA. Local conditions may vary. Last updated: May 2026.

Sources & credits

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