One of the best tools that you have as gardeners to help us estimate 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 getting a good idea when to plant primroses is to use the USDA zone info for Tolleson.

Planting Calendar for Primroses

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

You can plant primroses quite a bit earlier in the year because they do well in cold.

The earliest that you can plant primroses in Tolleson 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. Any later than that and your primroses may not have a chance to really do well. You can get started a few weeks earlier by starting your primroses indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Tolleson. It might get as low as 25°F during the coldest months of winter.

Keep in mind that USDA zone info for Tolleson may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Tolleson there is a last frost after February 15 so make sure that you are prepared to protect your primroses in the event of one of those late frosts.

USDA Zone Info for Tolleson

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Tolleson

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