When to Plant Tomatos in Hartford, WI

Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Hartford should be read to determine when it's a good idea to plant tomatos.


Planting Calendar for Tomatos

Frost tolerance for tomatos: Not tolerant of frost.
When to plant: After all chance of frost has passed.

You really shouldn't plant tomatos until after all chance of frost has passed because they are not cold tolerant.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant tomatos
Possibly ok, but a risky time to plant tomatos
Probably not a good time to plant tomatos

The earliest that you can plant tomatos in Hartford is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant tomatos and expect a good harvest is probably August. You probably don't want to wait any later than that or else your tomatos may not have a chance to grow to maturity. Starting your tomatos indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Hartford. You should expect an average low temperature of -20°F in the coldest months of winter.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Hartford and it changes from year to year. Since half of the time in Hartford there is a last frost after April 15 be ready to protect your tomatos in the event of a surprise late frost.

USDA Zone Info for Hartford

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Hartford

You may be interested in your other planting guides for Hartford.