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When to Plant Broccoli Rabe in Duchesne County, UT

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

Duchesne County, Utah is in USDA Zone 4b. The average last spring frost is May 10 and the first fall frost is October 4, giving you a growing season of approximately 147 days.

At an elevation of 5,302 feet, Duchesne County receives approximately 13 inches of rainfall annually with predominantly loam soil. Summer highs average 80ยฐF, so choose short-season varieties of Broccoli Rabe to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Broccoli Rabe successfully. Mulch heavily to conserve soil moisture.

Duchesne County, UT (Zone 4b) Short season
147 days
Last Spring Frost May 10
147 growing days
First Fall Frost October 4

Duchesne County Soil Profile

Soil Type

Loam

Soil pH

6.4-8.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (69 days to spare)
Start indoors: Mar 20 Transplant: May 1 🍅 Harvest: Jun 12 – Jul 17
Recommended (50%) ✓ Fits season (70 days to spare)
Start indoors: Mar 29 Transplant: May 10 🍅 Harvest: Jun 21 – Jul 26
Safe Start (90%) ✓ Fits season (59 days to spare)
Start indoors: Apr 23 Transplant: Jun 4 🍅 Harvest: Jul 16 – Aug 20

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 Duchesne County

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

Soil pH

Your soil pH (6.4โ€“8.2) overlaps with Broccoli Rabe's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

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

Organic Matter

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

How to Plant Broccoli Rabe

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

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Broccoli Rabe

4
successive plantings in your 147-day season

Sow every 4.6 weeks. Last sowing by Aug 05 to harvest before frost.

For a dedicated fall crop, sow by Jul 12.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.4″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 673 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

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 โ€” 0.9" 0" โ„๏ธ Dormant
Feb โ€” 0.8" 0" โ„๏ธ Dormant
Mar โ€” 1.3" 0" โ„๏ธ Dormant
Apr โ€” 1.4" 0" โ„๏ธ Dormant
May 3.5" 1.3" 2.2" ๐Ÿšฟ Regular watering
Jun 3.5" 0.8" 2.7" ๐Ÿšฟ Regular watering
Jul 3.5" 1.3" 2.2" ๐Ÿšฟ Regular watering
Aug 3.5" 1.3" 2.2" ๐Ÿšฟ Regular watering
Sep 3.5" 1.2" 2.3" ๐Ÿšฟ Regular watering
Oct 3.5" 1.3" 2.2" ๐Ÿšฟ Regular watering
Nov โ€” 1" 0" โ„๏ธ Dormant
Dec โ€” 0.6" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Duchesne County). Supplement amounts are based on average rainfall โ€” 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" 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.

Broccoli Rabe needs ~500 GDD — county provides 1,470 GDD Excellent fit

Broccoli Rabe Planting Timeline โ€” Duchesne County, UT

Broccoli Rabe Planting Calendar

Activity When Date Range
Start Indoors March 29 Mar 29 โ€“ Apr 12
Transplant Outdoors May 10 May 10 โ€“ May 24
Direct Sow May 3 May 3 โ€“ May 24
Harvest June 21 Jun 21 โ€“ Jul 26
Fall Sowing July 12 Jul 12 โ€“ Jul 26

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.8"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 4b

๐Ÿ“† Growing Season

147 days in Duchesne County

Growing Tips for Broccoli Rabe in Duchesne County

Direct sow Broccoli Rabe outdoors after May 10 in Duchesne County when soil has warmed and frost danger has passed.

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 Duchesne County, UT?

Duchesne County is in Zone 4b with an average last frost of May 10. Plan your Broccoli Rabe planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Duchesne County, UT?

Duchesne County, Utah is in USDA Hardiness Zone 4b. The average last spring frost is May 10 and first fall frost is October 4.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Duchesne County gardeners in Zone 4b organize planting dates, track what's growing, and never miss a planting window.

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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 Duchesne County, UT. Local conditions may vary. Last updated: April 2026.