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When to Plant Four-o-clock flower in Great Falls, MT

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 opportunity to plant four-o-clock flower in Great Falls can be figured out by checking out the USDA zone info.


Planting Calendar for Four-o-clock flower

Frost tolerance for four-o-clock flower: Not tolerant of frost.
When to plant: After the last frost when the weather gets warmer.

Four-o-clock flower are not cold tolerant which means that it is necessary to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant four-o-clock flower
Possibly ok, but a risky time to plant four-o-clock flower
Probably not a good time to plant four-o-clock flower

The earliest that you can plant four-o-clock flower in Great Falls is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant four-o-clock flower and expect a good harvest is probably August. You probably don't want to wait any later than that or else your four-o-clock flower may not have a chance to fully mature. You can get started a few weeks earlier by starting your four-o-clock flower indoors.

Last Frost Date

On average all chance of frost has passed is on May 15 in Great Falls. It might get as low as -30°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Great Falls and it will vary from year to year. Since half of the time in Great Falls you get a frost after May 15 be ready to protect your four-o-clock flower in the event of one of those late frosts.

USDA Zone Info for Great Falls

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-30°F
Highest Expected Low-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Great Falls

You may be interested in your other planting guides for Great Falls.