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 should be able to figure out when it's a good idea to plant bells of ireland by referring to the USDA zone info for Watertown.

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.

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

The earliest that you can plant bells of ireland in Watertown 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 bells of ireland and expect a good harvest is probably August. You probably don't want to wait any later than that or else your bells of ireland may not have a chance to really do well. Starting your bells of ireland indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Watertown the average date of last frost happens on April 15. You should expect an average low temperature of -20°F in the coldest months of winter.

It's important to remember that USDA zone info for Watertown is an average and the actual date of last frost changes from year to year. Half of the time in Watertown you get surprised by a frost after April 15 so just be sure to be ready to cover your bells of ireland if you have one of those late frosts.

USDA Zone Info for Watertown

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 Watertown

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