One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to determine when it's possible to plant dipladenia by looking at the USDA zone info for Boulder City.

Planting Calendar for Dipladenia

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

Since dipladenia do not do well in cold weather it is important to wait until after the last frost has passed before you can plant them.

The earliest that you can plant dipladenia in Boulder City is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant dipladenia and expect a good harvest is probably September. Any later than that and your dipladenia may not have a chance to grow to maturity. If you are starting your dipladenia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on February 15 in Boulder City. In the coldest months of winter you can expect an average low temperature of 25°F.

Since the USDA zone info for Boulder City is an average the actual date of last frost is different every year. Half of the time in Boulder City there is a last frost after February 15 so be sure to be ready to cover your dipladenia if you have one of those late frosts.

USDA Zone Info for Boulder City

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Boulder City

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