The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first chance to plant iresene in San Diego can be figured out by looking at the USDA zone info.

Planting Calendar for Iresene

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

Iresene are not cold tolerant which tells us that you must 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 iresene in San Diego 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 iresene and expect a good harvest is probably September. You probably don't want to wait any later than that or else your iresene may not have a chance to really do well. You can get started a few weeks earlier by starting your iresene indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in San Diego. It might get as low as 20°F during the coldest months of winter.

Remember that USDA zone info for San Diego may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in San Diego you get surprised by a frost after February 15 be ready to cover your iresene if you have one of those late frosts.

USDA Zone Info for San Diego

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 San Diego

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