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.

It's possible to figure out when it's possible to plant primula by looking at the USDA zone info for Wasco.

Planting Calendar for Primula

Frost tolerance for primula:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Primula do well in cold which means that you can get them planted much earlier than other frost tender plants.

The earliest that you can plant primula in Wasco 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 primula and expect a good harvest is probably October. If you wait any later than that and your primula may not have a chance to fully mature. You can get started a few weeks earlier by starting your primula indoors.

Last Frost Date

The average date of last frost is February 15 in Wasco. In the coldest months of winter you can expect an average low temperature of 20°F.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Wasco and it is different every year. Half of the time in Wasco there is a last frost after February 15 so make sure that you are prepared to protect your primula in the event of a late frost.

USDA Zone Info for Wasco

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 Wasco

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