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When to Plant Celeriac in Sherbrooke, QC

Celeriac is a celery relative grown for its knobby, flavorful root rather than its stalks. It has a rich celery flavor and is excellent roasted, mashed, or in soups.

Sherbrooke, Quebec is in USDA Zone 5b. The average last spring frost is April 23 and the first fall frost is October 7, giving you a growing season of approximately 167 days.

At an elevation of 738 feet, Sherbrooke receives approximately 30.7 inches of rainfall annually with predominantly gray-brown podzol soil. Summer highs average 74ยฐF, so choose short-season varieties of Celeriac to ensure they mature before fall.

Sherbrooke, QC (Zone 5b) Moderate season
167 days
Last Spring Frost April 23
167 growing days
First Fall Frost October 7

Sherbrooke Soil Profile

Soil Type

Gray-Brown Podzol

Soil pH

6.0-7.0

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (43 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: Jul 29 – Sep 2
Recommended (50%) ✓ Fits season (43 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: Jul 29 – Sep 2
Safe Start (90%) ✓ Fits season (43 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: Jul 29 – Sep 2

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.

How to Plant Celeriac

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

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

Plant Water Budget

Plant needs
0.9″/week
Rainfall provides
0.8″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 190 gal / 100 sq ft

Monthly Watering Guide for Celeriac

Celeriac needs approximately 0.9 inches of water per week (3.9" per month). Here's how your county's rainfall compares month by month.

Month Celeriac Needs Rainfall You Supplement Action
Jan โ€” 1.4" 0" โ„๏ธ Dormant
Feb โ€” 1.2" 0" โ„๏ธ Dormant
Mar โ€” 2.3" 0" โ„๏ธ Dormant
Apr 3.9" 3" 0.9" ๐Ÿ’ง Light watering
May 3.9" 3.9" 0" โœ… Rainfall sufficient
Jun 3.9" 4.1" 0" โœ… Rainfall sufficient
Jul 3.9" 3.4" 0.5" ๐Ÿ’ง Light watering
Aug 3.9" 2.7" 1.2" ๐Ÿ’ง Light watering
Sep 3.9" 2.6" 1.3" ๐Ÿ’ง Light watering
Oct 3.9" 2.1" 1.8" ๐Ÿ’ง Light watering
Nov โ€” 2" 0" โ„๏ธ Dormant
Dec โ€” 1.9" 0" โ„๏ธ Dormant

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

Celeriac 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.

Celeriac needs ~605 GDD — county provides 918 GDD Excellent fit

Celeriac Planting Timeline โ€” Sherbrooke, QC

Celeriac Planting Calendar

Activity When Date Range
Start Indoors March 19 Mar 19 โ€“ Apr 2
Transplant Outdoors April 23 Apr 23 โ€“ May 7
Direct Sow April 9 Apr 9 โ€“ Apr 30
Harvest August 6 Aug 6 โ€“ Sep 10
Fall Sowing July 29 Jul 29 โ€“ Aug 12

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 Transplant Outdoors Direct Sow
May Transplant Outdoors
June โ€”
July Fall Sowing
August Fall Sowing Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.9"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

100โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

167 days in Sherbrooke

Growing Tips for Celeriac in Sherbrooke

Common pests for Celeriac in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 10-12 weeks before last frost. Remove side roots as they develop to encourage a single large bulb. Harvest after a light frost for best flavor.

Companion Planting

Good Companions

Avoid Planting Near

  • Carrots
  • Parsnip

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Celeriac in Sherbrooke, QC?

Sherbrooke is in Zone 5b with an average last frost of April 23. Plan your Celeriac planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Sherbrooke, QC?

Sherbrooke, Quebec is in USDA Hardiness Zone 5b. The average last spring frost is April 23 and first fall frost is October 7.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Sherbrooke gardeners in Zone 5b 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 Sherbrooke, QC. Local conditions may vary. Last updated: April 2026.