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 Ironwood should be reffered to in order to determine when you can plant mustard greens.

Planting Calendar for Mustard greens

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

Mustard greens do well in moderate cold which means that you can start planting them earlier than other plants that might not handle the cold.

The earliest that you can plant mustard greens in Ironwood 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 mustard greens and expect a good harvest is probably August. Any later than that and your mustard greens may not have a chance to fully mature. Starting your mustard greens indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Remember that USDA zone info for Ironwood is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Ironwood you get surprised by a frost after May 15 be ready to cover your mustard greens if you have one of those late frosts.

USDA Zone Info for Ironwood

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 Ironwood

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