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.

By looking at the USDA zone info for Altoona it's possible to figure out when you can plant salpiglossis.

Planting Calendar for Salpiglossis

Frost tolerance for salpiglossis:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since salpiglossis are not cold tolerant it is important to wait until after the last frost before you can plant them.

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

The last month that you can plant salpiglossis and expect a good harvest is probably August. You probably don't want to wait any later than that or else your salpiglossis may not have a chance to fully mature. You can get started a little bit earlier by starting your salpiglossis indoors.

Last Frost Date

On average the last frost has passed is on May 15 in Altoona. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Altoona is an average the actual date of last frost changes from year to year. Since half of the time in Altoona last frost occurs after May 15 be ready to cover your salpiglossis in the event of a late frost.

USDA Zone Info for Altoona

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°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 -20°F.

Plants to Grow in Altoona

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