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

The first chance to plant gladiolus in Zone 5b should be figured out by referring to the USDA zone info.

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 slightly earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant gladiolus in Zone 5b 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 grow to maturity. You can get started a few weeks earlier by starting your gladiolus indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Zone 5b. You should expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Zone 5b is not always accurate and the actual date of last frost is different every year. Since half of the time in Zone 5b there is a last frost after April 15 be ready to protect your gladiolus in the event of one of those late frosts.

USDA Zone Info for Zone 5b

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 Zone 5b

You may be interested in your other planting guides for Zone 5b.