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

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

Planting Calendar for Scallions

Frost tolerance for scallions:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Scallions are one of those plants that can tolerate a tiny bit of cold weather which means that you can plant them slightly earlier than plants that are more sensitive to the cold.

The earliest that you can plant scallions in Altoona 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 scallions and expect a good harvest is probably August. If you wait any later than that and your scallions may not have a chance to really do well. You can get started a few weeks earlier by starting your scallions indoors.

Last Frost Date

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

It's important to remember that USDA zone info for Altoona is an average and the actual date of last frost will vary from year to year. Since half of the time in Altoona there is a last frost after April 15 be ready to cover your scallions in the event of 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.