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.

You will be able to estimate when to plant bells of ireland by referring to the USDA zone info for Altoona.

Planting Calendar for Bells of Ireland

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

Since bells of ireland do ok in moderate cold you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant bells of ireland 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 bells of ireland and expect a good harvest is probably August. Any later than that and your bells of ireland may not have a chance to really do well. If you are starting your bells of ireland indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Altoona the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Altoona and it is different every year. Half of the time in Altoona you get a frost after May 15 so be sure to be ready to cover your bells of ireland if you have a surprise 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.