Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Iron Mountain you can figure out when to plant sweet sultan by referring to the USDA zone info.

Planting Calendar for Sweet Sultan

Frost tolerance for sweet sultan:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since sweet sultan are barely cold tolerant you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant sweet sultan in Iron Mountain is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant sweet sultan and expect a good harvest is probably August. Any later than that and your sweet sultan may not have a chance to fully mature. Starting your sweet sultan indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Iron Mountain the average date of last frost happens on May 15. You can expect an average low temperature of -30°F in the coldest months of winter.

Always keep in mind that USDA zone info for Iron Mountain may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Iron Mountain there is a last frost after May 15 so make sure that you are ready to protect your sweet sultan if you have a surprise late frost.

USDA Zone Info for Iron Mountain

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 Iron Mountain

You may be interested in your other planting guides for Iron Mountain.