When to Plant Gladiolus in Zone 3b

One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can figure out when it's the best time to plant gladiolus in Zone 3b by looking at 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.

Gladiolus are barely cold tolerant which means that you can start planting them slightly earlier than plants that are more sensitive to the cold.

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

The earliest that you can plant gladiolus in Zone 3b 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 gladiolus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your gladiolus may not have a chance to fully mature. You can get started a little bit earlier by starting your gladiolus indoors.

Last Frost Date

On average all chance of frost has passed is on May 15 in Zone 3b. You can expect an average low temperature of -35°F in the coldest months of winter.

Since the USDA zone info for Zone 3b is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Zone 3b you get surprised by a frost after May 15 be ready to protect your gladiolus if you have a surprise late frost.

USDA Zone Info for Zone 3b

Here is the info for USDA Zone 3b.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-35°F
Highest Expected Low-30°F

This means that on a really cold year, the coldest it will get is -35°F. On most years you should be prepared to experience lows near -30°F.

Plants to Grow in Zone 3b

You may be interested in your other planting guides for Zone 3b.