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

You will be able to determine when to plant lemon balm by looking at the USDA zone info for Spearfish.

Planting Calendar for Lemon balm

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

You can plant lemon balm just a tiny bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant lemon balm in Spearfish 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 lemon balm and expect a good harvest is probably August. Any later than that and your lemon balm may not have a chance to fully mature. If you are starting your lemon balm indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Spearfish the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -20°F.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Spearfish and it will vary from year to year. Since half of the time in Spearfish it frosts late in the year after April 15 be ready to protect your lemon balm if you have a late frost.

USDA Zone Info for Spearfish

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Spearfish

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