One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can estimate when it's possible to plant alternaria in Presidio by looking at the USDA zone info.

Planting Calendar for Alternaria

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

Alternaria are not cold tolerant which tells us that it is important to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant alternaria in Presidio 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 alternaria and expect a good harvest is probably September. If you wait any later than that and your alternaria may not have a chance to fully mature. You can get started a few weeks earlier by starting your alternaria indoors.

Last Frost Date

On average the last frost is on February 15 in Presidio. You should expect an average low temperature of 20°F in the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Presidio and it changes from year to year. Since half of the time in Presidio there is a last frost after February 15 be ready to cover your alternaria in the event of a surprise late frost.

USDA Zone Info for Presidio

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Presidio

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