When to Plant Gladiolus in Zone 1b

One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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 determine when it's the best time to plant gladiolus in Zone 1b by checking out 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 tend to make it in mild cold which means that you can plant them slightly earlier in the year than other plants that might not handle 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 1b is June. However, you really should wait until July if you don't want to take any chances.

The last month that you can plant gladiolus and expect a good harvest is probably July. Any later than that and your gladiolus may not have a chance to really do well. 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

The average date of last frost is June 15 in Zone 1b. In the coldest months of winter you should expect an average low temperature of -55°F.

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 Zone 1b and it is different every year. Since half of the time in Zone 1b you get a frost after June 15 be ready to cover your gladiolus in the event of one of those late frosts.

USDA Zone Info for Zone 1b

Here is the info for USDA Zone 1b.

Average Date of Last Frost (spring)June 15
Average Date of First Frost (fall)July 15
Lowest Expected Low-55°F
Highest Expected Low-50°F

This means that on a really cold year, the coldest it will get is -55°F. On most years you should be prepared to experience lows near -50°F.

Plants to Grow in Zone 1b

You may be interested in your other planting guides for Zone 1b.