The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Hyrum should be looked at to estimate when it's a good idea to plant bok choi.

Planting Calendar for Bok Choi

Frost tolerance for bok choi:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since bok choi are one of those plants that can tolerate a little bit of cold weather you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant bok choi in Hyrum is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant bok choi and expect a good harvest is probably September. Any later than that and your bok choi may not have a chance to really do well. You can get started a couple of weeks earlier by starting your bok choi indoors.

Last Frost Date

The average date of last frost is April 15 in Hyrum. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Hyrum may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Hyrum you get surprised by a frost after April 15 so just be sure to be ready to cover your bok choi in the event of one of those late frosts.

USDA Zone Info for Hyrum

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 Hyrum

You may be interested in your other planting guides for Hyrum.