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.

The best time to plant purple coneflower in Robstown can be estimated by reviewing the USDA zone info.

Planting Calendar for Purple Coneflower

Frost tolerance for purple coneflower:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since purple coneflower do ok in moderate cold you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant purple coneflower in Robstown 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 purple coneflower and expect a good harvest is probably September. Any later than that and your purple coneflower may not have a chance to grow to maturity. Starting your purple coneflower indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost has passed is on February 15 in Robstown. It might get as low as 25°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Robstown is just an average and the actual date of last frost is different every year. Half of the time in Robstown last frost occurs after February 15 so just be sure to be ready to protect your purple coneflower in the event of a surprise late frost.

USDA Zone Info for Robstown

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 Robstown

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