One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Waterloo you can estimate when it's possible to plant purple bell vines by looking at the USDA zone info.

Planting Calendar for Purple Bell Vines

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

Since purple bell vines are barely cold tolerant you can plant them just a tiny bit earlier in the year than other frost tender plants.

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

Last Frost Date

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

It's important to remember that USDA zone info for Waterloo is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Waterloo you get surprised by a frost after April 15 be ready to cover your purple bell vines if you have a late frost.

USDA Zone Info for Waterloo

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 Waterloo

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