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 USDA zone info for Douglas should be read to estimate when to plant chrysocephalum.

Planting Calendar for Chrysocephalum

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

Since chrysocephalum are not cold tolerant you must wait until after the last frost has passed before you can plant them.

The earliest that you can plant chrysocephalum in Douglas is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant chrysocephalum and expect a good harvest is probably August. If you wait any later than that and your chrysocephalum may not have a chance to really do well. If you are starting your chrysocephalum indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on May 15 in Douglas. In the coldest months of winter you should expect an average low temperature of -25°F.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Douglas and it can change quite a bit from year to year. Since half of the time in Douglas you get surprised by a frost after May 15 be ready to protect your chrysocephalum if you have a surprise late frost.

USDA Zone Info for Douglas

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°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 -20°F.

Plants to Grow in Douglas

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