Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant helianthemum in Donna can be estimated by reviewing the USDA zone info.

Planting Calendar for Helianthemum

Frost tolerance for helianthemum:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Helianthemum are one of those plants that can tolerate a little bit of cold weather which tells us that you can plant them a little bit earlier than other plants that might not handle the cold.

The earliest that you can plant helianthemum in Donna 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 helianthemum and expect a good harvest is probably October. You probably don't want to wait any later than that or else your helianthemum may not have a chance to really do well. If you are starting your helianthemum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Donna is just an average the actual date of last frost is different every year. Since half of the time in Donna you get surprised by a frost after February 15 be ready to cover your helianthemum in the event of a surprise late frost.

USDA Zone Info for Donna

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 Donna

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