One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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.

The earliest that you can plant dahlia in Scottsdale should be estimated by checking out 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 require warm weather it's important to wait until after the last frost has passed before you can plant them.

The earliest that you can plant dahlia in Scottsdale 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. If you wait any later than that and your dahlia may not have a chance to really do well. Starting your dahlia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Scottsdale. In the coldest months of winter you can expect an average low temperature of 25°F.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Scottsdale and it is different every year. Since half of the time in Scottsdale there is a last frost after February 15 be ready to protect your dahlia in the event of a late frost.

USDA Zone Info for Scottsdale

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 Scottsdale

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