One of the best tools that you have as gardeners to help us figure out 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.

The first opportunity to plant nierembergia in El Cajon should be determined by looking at the USDA zone info.

Planting Calendar for Nierembergia

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

Since nierembergia are not cold tolerant it's important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant nierembergia in El Cajon 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 nierembergia and expect a good harvest is probably September. Any later than that and your nierembergia may not have a chance to really do well. If you are starting your nierembergia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on January 31 in El Cajon. It might get as low as 30°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for El Cajon and it can change quite a bit from year to year. Half of the time in El Cajon you get surprised by a frost after January 31 so always be ready to cover your nierembergia if you have one of those late frosts.

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.