Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You should be able to estimate when it's the best time to plant phlox by looking at the USDA zone info for El Cajon.

Planting Calendar for Phlox

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

Phlox do well in mild cold which tells us that you can plant them a little earlier in the year than other plants that might not handle the cold.

The earliest that you can plant phlox in El Cajon 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. If you wait any later than that and your phlox may not have a chance to fully mature. If you are starting your phlox indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is January 31 in El Cajon. It might get as low as 30°F during the coldest months of winter.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for El Cajon and it changes from year to year. Half of the time in El Cajon last frost occurs after January 31 so make sure that you are prepared to protect your phlox if you have a late frost.

USDA Zone Info for El Cajon

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in El Cajon

You may be interested in your other planting guides for El Cajon.