The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Boulder should be read to figure out when you can plant lantana.

Planting Calendar for Lantana

Frost tolerance for lantana:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Lantana require warm weather which means that it's necessary to wait until it warms up after the last frost has passed before you can plant them.

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

Last Frost Date

On average the last frost has passed is on April 15 in Boulder. You can expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Boulder and it can change quite a bit from year to year. Half of the time in Boulder it frosts late in the year after April 15 so always be ready to cover your lantana in the event of a surprise late frost.

USDA Zone Info for Boulder

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 Boulder

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