One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Spearfish you can estimate when it's possible to plant tomatos by checking out the USDA zone info.

Planting Calendar for Tomatos

Frost tolerance for tomatos:	Not tolerant of frost.
When to plant:	After the last frost.

Tomatos do not do well in cold weather which means that you need to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant tomatos in Spearfish 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 tomatos and expect a good harvest is probably August. Any later than that and your tomatos may not have a chance to grow to maturity. Starting your tomatos indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Spearfish. It might get as low as -20°F during the coldest months of winter.

Always keep in mind that USDA zone info for Spearfish may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Spearfish there is a last frost after April 15 so make sure that you are prepared to cover your tomatos in the event of one of those late frosts.

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.