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When to Plant New Zealand Spinach in Waukesha County, WI

Waukesha County, Wisconsin Zone 5b June

Your June gardening checklist

We've pulled the most time-sensitive tasks for Waukesha County, Wisconsin this June and put them front and centre. Tackle them in order.

Avg. last frost April 27
Avg. first frost October 12
Soil temp (4") 67°F
Watering Low
Pest pressure High
Daylight 15.2 hrs
  1. Get new zealand spinach seeds going inside

    Your window is short. These crops want several weeks of indoor growth before they go outside.

Coming up in July — start thinking about
  • 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.

Waukesha County, Wisconsin is in USDA Zone 5b. The average last spring frost is April 27 and the first fall frost is October 12, giving you a growing season of approximately 168 days.

At an elevation of 1,352 feet, Waukesha County receives approximately 37.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of New Zealand Spinach to ensure they mature before fall.

Waukesha County, WI (Zone 5b) Moderate season
168 days
Last Spring Frost April 27
168 growing days
First Fall Frost October 12

Waukesha County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-7.3

Drainage

Well Drained

New Zealand Spinach Planting Risk Windows

Early Start (70% safe) ✓ Fits season (69 days to spare)
Start indoors: Feb 26 Transplant: May 7 🍅 Harvest: Jul 2 – Jul 30
Recommended (50%) ✓ Fits season (70 days to spare)
Start indoors: Mar 2 Transplant: May 11 🍅 Harvest: Jul 6 – Aug 3
Safe Start (90%) ✓ Fits season (68 days to spare)
Start indoors: Mar 18 Transplant: May 27 🍅 Harvest: Jul 22 – Aug 19

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 Waukesha County

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

Soil pH

Your soil pH (6.1–7.3) is within New Zealand Spinach's preferred range (6.0–7.5).

Soil Texture

The silt loam soil in Waukesha 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 (4.2%) — 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 168-day season

Sow every 6.3 weeks. Last sowing by Aug 03 to harvest before frost.

New Zealand Spinach Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 549 gal / 100 sq ft

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 1.7" 0" ❄️ Dormant
Feb 1.8" 0" ❄️ Dormant
Mar 2.8" 0" ❄️ Dormant
Apr 4.3" 3.4" 0.9" 💧 Light watering
May 4.3" 4.3" 0" ✅ Rainfall sufficient
Jun 4.3" 4.5" 0" ✅ Rainfall sufficient
Jul 4.3" 4" 0.3" 💧 Light watering
Aug 4.3" 3.7" 0.6" 💧 Light watering
Sep 4.3" 3.2" 1.1" 💧 Light watering
Oct 4.3" 3.2" 1.1" 💧 Light watering
Nov 2.6" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Waukesha 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 ~766 GDD — county provides 2,058 GDD Excellent fit

New Zealand Spinach Planting Timeline — Waukesha County, WI

New Zealand Spinach Planting Calendar

Activity When Date Range
Start Indoors March 2 Mar 2 – Mar 16
Transplant Outdoors May 11 May 11 – May 25
Direct Sow May 4 May 4 – May 25
Harvest July 6 Jul 6 – Aug 3

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

55–70 days

🧪 Soil pH

Needs 6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 5b

📆 Growing Season

168 days in Waukesha County

Growing Tips for New Zealand Spinach in Waukesha County

Direct sow New Zealand Spinach outdoors after April 27 in Waukesha 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 Waukesha County, WI?

Waukesha County is in Zone 5b with an average last frost of April 27. Plan your New Zealand Spinach planting based on this frost date — see the calendar above for exact timing.

What planting zone is Waukesha County, WI?

Waukesha County, Wisconsin is in USDA Hardiness Zone 5b. The average last spring frost is April 27 and first fall frost is October 12.

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Your Waukesha County Garden Planner — Free

A 22-page printable planner built for Waukesha 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 Waukesha County, WI. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.