One of the best tools that you have as gardeners to help us determine 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.

In Lewistown you can figure out when it's the best time to plant mustard by reviewing the USDA zone info.

Planting Calendar for Mustard

Frost tolerance for mustard:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since mustard require warm weather you really should wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant mustard in Lewistown 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 mustard and expect a good harvest is probably August. Any later than that and your mustard may not have a chance to grow to maturity. Starting your mustard indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Lewistown. It might get as low as -30°F during the coldest months of winter.

Since the USDA zone info for Lewistown is just an average the actual date of last frost will vary from year to year. Since half of the time in Lewistown you get surprised by a frost after May 15 be ready to protect your mustard if you have one of those late frosts.

USDA Zone Info for Lewistown

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 Lewistown

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