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 Spearfish you can determine when it's a good idea to plant amaranthus by reviewing the USDA zone info.

Planting Calendar for Amaranthus

Frost tolerance for amaranthus:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since amaranthus are not cold tolerant it's important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant amaranthus 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 amaranthus and expect a good harvest is probably August. If you wait any later than that and your amaranthus may not have a chance to fully mature. If you are starting your amaranthus indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

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

Remember that USDA zone info for Spearfish may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Spearfish you get a frost after April 15 so make sure that you are ready to cover your amaranthus 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.