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 earliest that you can plant alternaria in Douglas can be figured out by referring to the USDA zone info.

Planting Calendar for Alternaria

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

You can not plant alternaria until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant alternaria 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 alternaria and expect a good harvest is probably August. You probably don't want to wait any later than that or else your alternaria may not have a chance to really do well. If you are starting your alternaria indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Douglas. It might get as low as -25°F during the coldest months of winter.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Douglas and it changes from year to year. Half of the time in Douglas there is a last frost after May 15 so make sure that you are ready to protect your alternaria in the event of 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.