When can I plant Gladiolus in Zone 5a

One of the best tools that we have as gardeners to help us estimate our 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 our area.

The USDA zone info for Zone 5a can be reffered to in order to determine when it's possible to plant gladiolus.


Planting Calendar for Gladiolus

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

Since gladiolus are barely cold tolerant you can plant them slightly earlier in the year than more sensitive plants.

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 5a 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. If you are starting your gladiolus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Zone 5a the average date of last frost happens on April 15. We can expect an average low temperature of -20°F in the coldest months of winter.

Keep in mind that USDA zone info for Zone 5a may not be accurate from year to year and our actual date of last frost is different every year. Half of the time in Zone 5a we get a frost after April 15 so just be sure to be ready to cover your gladiolus in the event of one of those late frosts.

USDA Zone Info for Zone 5a

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 Zone 5a

You may be interested in our other planting guides for Zone 5a.