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.

The first chance to plant dahlia in Commerce City should be estimated by referring to the USDA zone info.

Planting Calendar for Dahlia

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

You really shouldn't plant dahlia until after the last frost when the weather gets warmer because they are not cold tolerant.

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

Last Frost Date

On average the last frost has passed is on April 15 in Commerce City. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Commerce City may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Commerce City last frost occurs after April 15 be ready to protect your dahlia if you have a late frost.

USDA Zone Info for Commerce City

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 Commerce City

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