One of the best tools that you have as gardeners to help us determine 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 earliest that you can plant schizanthus in Denver should be estimated by referring to the USDA zone info.

Planting Calendar for Schizanthus

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

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

The earliest that you can plant schizanthus in Denver 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 schizanthus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your schizanthus may not have a chance to really do well. You can get started a couple of weeks earlier by starting your schizanthus indoors.

Last Frost Date

The average date of last frost is April 15 in Denver. In the coldest months of winter you can expect an average low temperature of -15°F.

It's important to remember that USDA zone info for Denver is an average and the actual date of last frost will vary from year to year. Half of the time in Denver you get a frost after April 15 so just be sure to be ready to cover your schizanthus in the event of a surprise late frost.

USDA Zone Info for Denver

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 Denver

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