One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to determine when it's the best time to plant evolvulus by referring to the USDA zone info for Colby.

Planting Calendar for Evolvulus

Frost tolerance for evolvulus:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Evolvulus require warm weather which means that it is important to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant evolvulus in Colby 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 evolvulus and expect a good harvest is probably August. If you wait any later than that and your evolvulus may not have a chance to grow to maturity. You can get started a little bit earlier by starting your evolvulus indoors.

Last Frost Date

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

Keep in mind that USDA zone info for Colby is just an average and the actual date of last frost changes from year to year. Half of the time in Colby you get a frost after April 15 so just be sure to be ready to cover your evolvulus if you have a surprise late frost.

USDA Zone Info for Colby

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Colby

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