The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Altoona you can estimate when it's a good idea to plant phlox by referring to the USDA zone info.

Planting Calendar for Phlox

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

Phlox do well in mild cold which tells us that you can plant them a little bit earlier in the year than plants that are more sensitive to the cold.

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

The last month that you can plant phlox and expect a good harvest is probably September. If you wait any later than that and your phlox may not have a chance to really do well. If you are starting your phlox indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Altoona. In the coldest months of winter you should expect an average low temperature of -20°F.

It's important to remember that USDA zone info for Altoona is just an average and the actual date of last frost will vary from year to year. Half of the time in Altoona it frosts late in the year after April 15 so make sure that you are ready to cover your phlox 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.