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.

In San Francisco you can determine when it's possible to plant tropical water plants by referring to the USDA zone info.

Planting Calendar for Tropical Water Plants

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

Tropical Water Plants require warm weather which means that you really should wait until it warms up after the last frost before you can plant them.

The earliest that you can plant tropical water plants in San Francisco is February. However, you really should wait until March 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. You probably don't want to wait any later than that or else your tropical water plants may not have a chance to grow to maturity. If you are starting your tropical water plants indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on January 31 in San Francisco. It might get as low as 35°F during the coldest months of winter.

Keep in mind that USDA zone info for San Francisco is just an average and the actual date of last frost is different every year. Since half of the time in San Francisco it frosts late in the year after January 31 be ready to cover your tropical water plants in the event of one of those late frosts.

USDA Zone Info for San Francisco

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in San Francisco

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