One of the first steps you take when you are figuring out your gardening schedule is find your 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.

It's a good idea to estimate when it's a good idea to plant penstemon by looking at the USDA zone info for Merced.

Planting Calendar for Penstemon

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

Penstemon are moderately cold tolerant which means that you can get them planted earlier than other plants that might not handle the cold.

The earliest that you can plant penstemon in Merced 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 penstemon and expect a good harvest is probably October. If you wait any later than that and your penstemon may not have a chance to fully mature. Starting your penstemon indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Merced. In the coldest months of winter you should expect an average low temperature of 20°F.

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 Merced and it will vary from year to year. Since half of the time in Merced last frost occurs after February 15 be ready to protect your penstemon in the event of one of those late frosts.

USDA Zone Info for Merced

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 Merced

You may be interested in your other planting guides for Merced.