Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Iron Mountain you can figure out when you can plant tarragon by reviewing the USDA zone info.

Planting Calendar for Tarragon

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

You can plant tarragon slightly earlier in the year because they are barely cold tolerant.

The earliest that you can plant tarragon 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 tarragon and expect a good harvest is probably August. Any later than that and your tarragon may not have a chance to really do well. If you are starting your tarragon indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Iron Mountain. In the coldest months of winter you should expect an average low temperature of -30°F.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Iron Mountain and it can change quite a bit from year to year. Half of the time in Iron Mountain last frost occurs after May 15 so make sure that you are prepared to protect your tarragon 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.