One of the best tools that you have as gardeners to help us determine 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.

One way of getting a good idea when it's possible to plant browallia is to use the USDA zone info for Tucson.

Planting Calendar for Browallia

Frost tolerance for browallia:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's not a good idea to plant browallia until after the last frost has passed because they require warm weather.

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

Last Frost Date

The average date of last frost is February 15 in Tucson. It might get as low as 25°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Tucson and it can change quite a bit from year to year. Half of the time in Tucson you get surprised by a frost after February 15 so be sure to be ready to protect your browallia in the event of a surprise late frost.

USDA Zone Info for Tucson

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 Tucson

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