The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of estimating when it's the best time to plant gladiolus is to look at the USDA zone info for Janesville.

Planting Calendar for Gladiolus

Frost tolerance for gladiolus:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant gladiolus a bit earlier in the year because they do ok in moderate cold.

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

The last month that you can plant gladiolus and expect a good harvest is probably August. If you wait any later than that and your gladiolus may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your gladiolus indoors.

Last Frost Date

In Janesville the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -20°F.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Janesville and it can change quite a bit from year to year. Since half of the time in Janesville it frosts late in the year after April 15 be ready to cover your gladiolus in the event of one of those late frosts.

USDA Zone Info for Janesville

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 Janesville

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