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When to Plant New Zealand Spinach in Iroquois County, IL

Iroquois County, Illinois Zone 5b May

May to-do list for Iroquois County, Illinois

If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.

Avg. last frost April 18
Avg. first frost October 13
Soil temp (4") 58°F
Watering Low
Pest pressure Low
Daylight 14.3 hrs
  1. Move new zealand spinach from tray to bed

    Plant tomatoes deep — bury the stem up to the first true leaves to grow extra roots. Everything else goes in at the same depth it grew in the tray.

Get ahead of June
  • Starting indoors: new zealand spinach
  • First harvests: new zealand spinach

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New Zealand spinach is a heat-tolerant ground-cover plant with thick, triangular leaves that taste similar to true spinach. It thrives in hot weather when regular spinach bolts.

Iroquois County, Illinois is in USDA Zone 5b. The average last spring frost is April 18 and the first fall frost is October 13, giving you a growing season of approximately 178 days.

At an elevation of 1,345 feet, Iroquois County receives approximately 30 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for New Zealand Spinach during the growing season.

Iroquois County, IL (Zone 5b) Moderate season
178 days
Last Spring Frost April 18
178 growing days
First Fall Frost October 13
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Iroquois County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (80 days to spare)
Start indoors: Feb 16 Transplant: Apr 27 🍅 Harvest: Jun 22 – Jul 20
Recommended (50%) ✓ Fits season (80 days to spare)
Start indoors: Feb 21 Transplant: May 2 🍅 Harvest: Jun 27 – Jul 25
Safe Start (90%) ✓ Fits season (78 days to spare)
Start indoors: Mar 11 Transplant: May 20 🍅 Harvest: Jul 15 – Aug 12

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 Iroquois County

How your county's soil matches New Zealand Spinach's growing requirements.

Soil pH

Your soil pH (5.9–6.7) overlaps with New Zealand Spinach's range (6.0–7.5), though not a perfect match.

Soil Texture

The silt loam soil in Iroquois County is excellent for New Zealand Spinach — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for New Zealand Spinach.

Organic Matter

Organic matter is excellent (4.5%) — New Zealand Spinach will thrive.

How to Plant New Zealand Spinach

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

Succession Planting New Zealand Spinach

3
successive plantings in your 178-day season

Sow every 6.3 weeks. Last sowing by Aug 04 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.7″/week
Watering frequency 2-3 times/week
Season total 1,126 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for New Zealand Spinach

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

Month New Zealand Spinach Needs Rainfall You Supplement Action
Jan 1.3" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 4.3" 2.8" 1.5" 💧 Light watering
May 4.3" 3.8" 0.5" 💧 Light watering
Jun 4.3" 3.6" 0.7" 💧 Light watering
Jul 4.3" 3" 1.3" 💧 Light watering
Aug 4.3" 2.9" 1.4" 💧 Light watering
Sep 4.3" 3.2" 1.1" 💧 Light watering
Oct 4.3" 2.5" 1.8" 💧 Light watering
Nov 2" 0" ❄️ Dormant
Dec 1.6" 0" ❄️ Dormant

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

New Zealand Spinach 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.

New Zealand Spinach needs ~859 GDD — county provides 2,447 GDD Excellent fit

New Zealand Spinach Planting Timeline — Iroquois County, IL

New Zealand Spinach Planting Calendar

Activity When Date Range
Start Indoors February 21 Feb 21 – Mar 7
Transplant Outdoors May 2 May 2 – May 16
Direct Sow April 25 Apr 25 – May 16
Harvest June 27 Jun 27 – Jul 25

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 2-3 times/week

📅 Days to Maturity

55–70 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 5b

📆 Growing Season

178 days in Iroquois County

Growing Tips for New Zealand Spinach in Iroquois County

Direct sow New Zealand Spinach outdoors after April 18 in Iroquois County when soil has warmed and frost danger has passed.

General growing tips

Soak seeds overnight before planting. Direct sow after last frost. Pinch growing tips regularly to encourage bushy growth and tender new leaves.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant New Zealand Spinach in Iroquois County, IL?

Iroquois County is in Zone 5b with an average last frost of April 18. Plan your New Zealand Spinach planting based on this frost date — see the calendar above for exact timing.

What planting zone is Iroquois County, IL?

Iroquois County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 18 and first fall frost is October 13.

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Your Iroquois County Garden Planner — Free

A 24-page printable planner built for Iroquois 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 Iroquois County, IL. 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.