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.

It's a good idea to figure out when it's the best time to plant phlox by referring to the USDA zone info for San Juan.

Planting Calendar for Phlox

Frost tolerance for phlox:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since phlox are one of those plants that can tolerate a little bit of cold weather you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant phlox in San Juan is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant phlox and expect a good harvest is probably October. You probably don't want to wait any later than that or else your phlox may not have a chance to really do well. You can get started a couple of weeks earlier by starting your phlox indoors.

Last Frost Date

The average date of last frost is February 15 in San Juan. It might get as low as 25°F during the coldest months of winter.

Remember that USDA zone info for San Juan may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in San Juan it frosts late in the year after February 15 be ready to cover your phlox in the event of a late frost.

USDA Zone Info for San Juan

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 Juan

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