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

A common way of making a decision about when it's the best time to plant primroses is to look at the USDA zone info for Chino Hills.

Planting Calendar for Primroses

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

Primroses do well in pretty solid cold which tells us that you can plant them a lot earlier in the year than other frost tender plants.

The earliest that you can plant primroses in Chino Hills 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 primroses and expect a good harvest is probably October. If you wait any later than that and your primroses may not have a chance to grow to maturity. If you are starting your primroses indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Chino Hills the average date of last frost happens on January 31. In the coldest months of winter you can expect an average low temperature of 30°F.

It's important to remember that USDA zone info for Chino Hills may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Chino Hills you get surprised by a frost after January 31 be ready to cover your primroses if you have a late frost.

USDA Zone Info for Chino Hills

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 Chino Hills

You may be interested in your other planting guides for Chino Hills.