One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of figuring out when to plant gladiolus is to use the USDA zone info for Caledonia.

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.

Gladiolus do ok in moderate cold which tells us that you can get them planted just a bit earlier than more sensitive plants.

The earliest that you can plant gladiolus in Caledonia 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. Any later than that and your gladiolus may not have a chance to fully mature. If you are starting your gladiolus indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Caledonia the average date of last frost happens on April 15. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Caledonia may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Caledonia you get a frost after April 15 be ready to cover your gladiolus in the event of one of those late frosts.

USDA Zone Info for Caledonia

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Caledonia

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