Before planting it is a good idea to find your USDA Zone info to estimate 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.

The first opportunity to plant romaine lettuce in Spearfish can be determined by using the USDA zone info.

Planting Calendar for Romaine lettuce

Frost tolerance for romaine lettuce:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

You can plant romaine lettuce much earlier in the year because they are very cold tolerant.

The earliest that you can plant romaine lettuce in Spearfish is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant romaine lettuce and expect a good harvest is probably September. You probably don't want to wait any later than that or else your romaine lettuce may not have a chance to really do well. You can get started a few weeks earlier by starting your romaine lettuce indoors.

Last Frost Date

The average date of last frost is April 15 in Spearfish. You can expect an average low temperature of -20°F in the coldest months of winter.

Remember that the actual date of last frost is just an average 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 there is a last frost after April 15 be ready to protect your romaine lettuce in the event of 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.