One of the first steps you take when you are estimating 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.

A common way of determining when it's possible to plant primula is to use the USDA zone info for Grapevine.

Planting Calendar for Primula

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

You can plant primula much earlier in the year because they are very cold tolerant.

The earliest that you can plant primula in Grapevine 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 primula and expect a good harvest is probably September. You probably don't want to wait any later than that or else your primula may not have a chance to fully mature. Starting your primula indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Grapevine the average date of last frost happens on March 15. In the coldest months of winter you should expect an average low temperature of 10°F.

Keep in mind that USDA zone info for Grapevine is not always accurate and the actual date of last frost is different every year. Half of the time in Grapevine last frost occurs after March 15 so always be ready to cover your primula in the event of a surprise late frost.

USDA Zone Info for Grapevine

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Grapevine

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