One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for San Diego should be reffered to in order to figure out when you can plant tropical water plants.

Planting Calendar for Tropical Water Plants

Frost tolerance for tropical water plants:	Not tolerant of frost.
When to plant:	After the last frost.

Tropical Water Plants are not cold tolerant which tells us that you have 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 tropical water plants 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 tropical water plants and expect a good harvest is probably September. Any later than that and your tropical water plants may not have a chance to really do well. If you are starting your tropical water plants indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is February 15 in San Diego. You can expect an average low temperature of 20°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for San Diego and it will vary from year to year. Half of the time in San Diego you get a frost after February 15 so always be ready to cover your tropical water plants 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.