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When to Plant Broccoli Rabe in Lewis County, WA

Lewis County, Washington Zone 8a May

Your May game plan for Lewis County, Washington

Your Lewis County, Washington garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.

Avg. last frost April 25
Avg. first frost October 24
Soil temp (4") 66°F
Watering High
Pest pressure Moderate
Daylight 14.8 hrs
  1. Fire up the seed-starting tray: broccoli rabe

    These need a head start before your last frost (April 25). Sow into cells now so you're ready to transplant in a few weeks.

To set up a strong June, finish these tasks
  • First harvests: broccoli rabe

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Broccoli rabe (rapini) is a brassica grown for its slightly bitter, nutty-flavored florets, leaves, and stems. It is a staple in Italian cooking.

Lewis County, Washington is in USDA Zone 8a. The average last spring frost is April 25 and the first fall frost is October 24, giving you a growing season of approximately 182 days.

At an elevation of 327 feet, Lewis County receives approximately 37.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Broccoli Rabe during the growing season.

Lewis County, WA (Zone 8a) Moderate season
182 days
Last Spring Frost April 25
182 growing days
First Fall Frost October 24

Lewis County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (93 days to spare)
Start indoors: Mar 9 Transplant: Apr 13 🍅 Harvest: May 25 – Jun 29
Recommended (50%) ✓ Fits season (105 days to spare)
Start indoors: Mar 21 Transplant: Apr 25 🍅 Harvest: Jun 6 – Jul 11
Safe Start (90%) ✓ Fits season (73 days to spare)
Start indoors: May 20 Transplant: Jun 24 🍅 Harvest: Aug 5 – Sep 9

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 Lewis County

How your county's soil matches Broccoli Rabe's growing requirements.

Soil pH

Your soil pH (5.6–6.2) is more acidic than Broccoli Rabe prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is excellent (5.3%) — Broccoli Rabe will thrive.

How to Plant Broccoli Rabe

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Broccoli Rabe

5
successive plantings in your 182-day season

Sow every 4.6 weeks. Last sowing by Aug 25 to harvest before frost.

For a dedicated fall crop, sow by Aug 15.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Broccoli Rabe

Broccoli Rabe needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Broccoli Rabe Needs Rainfall You Supplement Action
Jan 5.6" 0" ❄️ Dormant
Feb 3.6" 0" ❄️ Dormant
Mar 4.1" 0" ❄️ Dormant
Apr 3.5" 2.8" 0.7" 💧 Light watering
May 3.5" 2" 1.5" 💧 Light watering
Jun 3.5" 1.3" 2.2" 🚿 Regular watering
Jul 3.5" 0.6" 2.9" 🚿 Regular watering
Aug 3.5" 0.6" 2.9" 🚿 Regular watering
Sep 3.5" 1.4" 2.1" 🚿 Regular watering
Oct 3.5" 3.4" 0.1" 💧 Light watering
Nov 6.3" 0" ❄️ Dormant
Dec 5.7" 0" ❄️ Dormant

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

Broccoli Rabe 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.

Broccoli Rabe needs ~725 GDD — county provides 2,639 GDD Excellent fit

Broccoli Rabe Planting Timeline — Lewis County, WA

Broccoli Rabe Planting Calendar

Activity When Date Range
Start Indoors March 21 Mar 21 – Apr 4
Transplant Outdoors April 25 Apr 25 – May 9
Direct Sow April 11 Apr 11 – May 2
Harvest June 6 Jun 6 – Jul 11
Fall Sowing August 15 Aug 15 – Aug 29

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · Natural rainfall sufficient

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 8a

📆 Growing Season

182 days in Lewis County

Growing Tips for Broccoli Rabe in Lewis County

Direct sow Broccoli Rabe outdoors after April 25 in Lewis County when soil has warmed and frost danger has passed.

Your generous 182.0-day season in Lewis County allows multiple plantings of Broccoli Rabe. Sow every 20.0 days for continuous harvest.

Common pests for Broccoli Rabe in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in spring or fall. Harvest when small yellow flower buds first appear but before they open. Cut the main shoot first to encourage side shoots.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Broccoli Rabe in Lewis County, WA?

Lewis County is in Zone 8a with an average last frost of April 25. Plan your Broccoli Rabe planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lewis County, WA?

Lewis County, Washington is in USDA Hardiness Zone 8a. The average last spring frost is April 25 and first fall frost is October 24.

🌱

Your Lewis County Garden Planner — Free

A 24-page printable planner built for Lewis County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Lewis County, WA. 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.