The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Rosenberg you can determine when it's a good idea to plant dahlia by reviewing the USDA zone info.

Planting Calendar for Dahlia

Frost tolerance for dahlia:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since dahlia do not do well in cold weather it is necessary to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant dahlia in Rosenberg is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant dahlia and expect a good harvest is probably September. You probably don't want to wait any later than that or else your dahlia may not have a chance to fully mature. If you are starting your dahlia indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Rosenberg. You can expect an average low temperature of 20°F in the coldest months of winter.

Always keep in mind that USDA zone info for Rosenberg may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Rosenberg you get a frost after February 15 be ready to cover your dahlia in the event of a late frost.

USDA Zone Info for Rosenberg

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Rosenberg

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