The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. 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 alternaria in San Jose can be determined by reviewing the USDA zone info.

Planting Calendar for Alternaria

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

Alternaria require warm weather which means that you need to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant alternaria in San Jose 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 grow to maturity. If you are starting your alternaria indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In San Jose the average date of last frost happens on February 15. You can expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for San Jose is not always accurate the actual date of last frost will vary from year to year. Half of the time in San Jose you get a frost after February 15 so just be sure to be ready to protect your alternaria in the event of one of those late frosts.

USDA Zone Info for San Jose

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°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 30°F.

Plants to Grow in San Jose

You may be interested in your other planting guides for San Jose.