One of the first steps you take when you are figuring out your gardening schedule is find your 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 first opportunity to plant dahlias in Altoona can be estimated by looking at the USDA zone info.

Planting Calendar for Dahlias

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

Dahlias are not cold tolerant which means that you have to wait until it warms up after the last frost has passed before you can plant them.

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

The last month that you can plant dahlias and expect a good harvest is probably August. If you wait any later than that and your dahlias may not have a chance to really do well. If you are starting your dahlias 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 April 15 in Altoona. You can expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Altoona is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Altoona you get surprised by a frost after April 15 be ready to protect your dahlias if you have a late frost.

USDA Zone Info for Altoona

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°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 -15°F.

Plants to Grow in Altoona

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