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When to plant Daikon in Saint Augustine, IL

Saint Augustine gardeners should plant Daikon between April 3 and April 24 in spring. With Saint Augustine's Zone 5b climate (last frost April 17), Daikon needs 50–70 days to mature — plant by August 6 for a full harvest. A second sowing from August 6 to August 20 extends the harvest into fall.

When to Plant Daikon in Saint Augustine, IL

Daikon is a large, mild Japanese radish that can grow over a foot long. It is excellent for pickling, stir-fries, and as a soil-breaking cover crop.

Saint Augustine, Illinois is in USDA Zone 5b. The average last spring frost is April 17 and the first fall frost is October 15, giving you a growing season of approximately 181 days.

At an elevation of 1,301 feet, Knox County receives approximately 33.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Daikon to ensure they mature before fall.

Saint Augustine, IL (Zone 5b) Moderate season
181 days
Last Spring Frost April 17
181 growing days
First Fall Frost October 15

Saint Augustine Soil Profile

Soil Type

Silt Loam

Soil pH

6-6.8

Drainage

Well Drained

Monthly Watering Guide for Daikon

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

Month Daikon Needs Rainfall You Supplement Action
Jan 1.3" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.4" 0" ❄️ Dormant
Apr 4.3" 3.4" 0.9" 💧 Light watering
May 4.3" 3.9" 0.4" 💧 Light watering
Jun 4.3" 3.6" 0.7" 💧 Light watering
Jul 4.3" 4.1" 0.2" 💧 Light watering
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 2.6" 1.7" 💧 Light watering
Oct 4.3" 2.7" 1.6" 💧 Light watering
Nov 2.5" 0" ❄️ Dormant
Dec 1.6" 0" ❄️ Dormant

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

Daikon Planting Timeline — Saint Augustine, IL

Daikon Planting Calendar

Activity When Date Range
Direct Sow April 3 Apr 3 – Apr 24
Harvest May 29 May 29 – Jun 26
Fall Sowing August 6 Aug 6 – Aug 20

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.8–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5b

📆 Growing Season

181 days in Knox County

Growing Tips for Saint Augustine

Direct sow in late summer for fall harvest. Loosen soil deeply before planting. Thin seedlings to 6 inches apart. Harvest before hard freeze as exposed shoulders may crack.

Companion Planting

Good Companions

Avoid Planting Near

  • Hyssop

Check more plant combinations with our Companion Planting Checker →

When should I plant Daikon in Saint Augustine, IL?

In Saint Augustine, IL, plant Daikon after the last frost (around April 17) and before the first frost (around October 15). Best results when soil holds above 50°F.

What growing zone is Saint Augustine, IL for Daikon?

Saint Augustine sits in USDA Zone 5b. Daikon grows reliably in zones 2a through 11b, so it's a good fit here.

Can Daikon grow in Saint Augustine's climate?

Yes — Daikon grows well in Saint Augustine's temperate climate. Saint Augustine averages a 181-day frost-free season, with last frost around April 17 and first frost around October 15.

🌱

Your Knox County Garden Planner — Free

A 22-page printable planner built for Knox County (Zone 5b). 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 Knox County, IL. Local conditions may vary. Last updated: June 2026.