When to Plant Tomatoes in Fond du Lac County, WI
This month in Fond du Lac County, Wisconsin
April is a pivotal month for Fond du Lac County, Wisconsin gardens. Focus on these tasks first and you'll set up the rest of the season for success.
Before May arrives, get these ready
- Transplants going out: tomatoes
- Direct-sowing: tomatoes
Tomatoes are the most popular home garden crop, available in thousands of varieties from tiny cherries to massive beefsteaks. They are warm-season plants needing full sun.
Fond du Lac County, Wisconsin is in USDA Zone 4b. The average last spring frost is April 27 and the first fall frost is October 14, giving you a growing season of approximately 170 days.
At an elevation of 713 feet, Fond du Lac County receives approximately 32.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Tomatoes to ensure they mature before fall.
Fond du Lac County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7.2
Drainage
Well Drained
Plant Planting Risk Windows
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 Fond du Lac County
How your county's soil matches Tomatoes's growing requirements.
Soil pH
Your soil pH (6.2–7.2) overlaps with Tomatoes's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Fond du Lac County is excellent for Tomatoes — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.1%) — Tomatoes will thrive.
How to Plant Tomatoes
Succession Planting Tomatoes
Sow every 6.9 weeks. Last sowing by Jul 21 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Tomatoes
Tomatoes needs approximately 1.2 inches of water per week (5.2" per month). Here's how your county's rainfall compares month by month.
| Month | Tomatoes Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.2" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | 5.2" | 3.5" | 1.7" | 💧 Light watering |
| May | 5.2" | 3.2" | 2" | 💧 Light watering |
| Jun | 5.2" | 4.4" | 0.8" | 💧 Light watering |
| Jul | 5.2" | 3.7" | 1.5" | 💧 Light watering |
| Aug | 5.2" | 3.4" | 1.8" | 💧 Light watering |
| Sep | 5.2" | 2.7" | 2.5" | 💧 Light watering |
| Oct | 5.2" | 2.8" | 2.4" | 💧 Light watering |
| Nov | — | 2.2" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Fond du Lac County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Tomatoes 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.
Tomatoes Planting Timeline — Fond du Lac County, WI
Tomatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 23 | Feb 23 – Mar 9 |
| Transplant Outdoors | May 18 | May 18 – Jun 1 |
| Direct Sow | May 11 | May 11 – Jun 1 |
| Harvest | July 20 | Jul 20 – Sep 28 |
Plant 0.5" deep · 24" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.2"/week · 1-2 times/week
📅 Days to Maturity
60–85 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 4b
📆 Growing Season
170 days in Fond du Lac County
Growing Tips for Tomatoes in Fond du Lac County
Direct sow Tomatoes outdoors after April 27 in Fond du Lac County when soil has warmed and frost danger has passed.
Common pests for Tomatoes in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 6-8 weeks before last frost. Bury transplants deep to encourage rooting along the stem. Provide consistent moisture to prevent blossom end rot and cracking.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Isolate 25 ft between varieties for purity. Use open-pollinated varieties for true-to-type seeds.
Tomatoes in Other Locations
Frequently Asked Questions
When should I plant Tomatoes in Fond du Lac County, WI?
Fond du Lac County is in Zone 4b with an average last frost of April 27. Plan your Tomatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Fond du Lac County, WI?
Fond du Lac County, Wisconsin is in USDA Hardiness Zone 4b. The average last spring frost is April 27 and first fall frost is October 14.
Your Fond du Lac County Garden Planner — Free
A 24-page printable planner built for Fond du Lac County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.