One of the first steps you take when you are making a decision about your gardening schedule is find your 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.

A way of making a decision about when it's the best time to plant pentas is to use the USDA zone info for Waterloo.

Planting Calendar for Pentas

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

Since pentas do not do well in cold weather you need to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant pentas in Waterloo 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 pentas and expect a good harvest is probably August. If you wait any later than that and your pentas may not have a chance to really do well. Starting your pentas indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Waterloo. It might get as low as -20°F during the coldest months of winter.

Remember that USDA zone info for Waterloo is an average and the actual date of last frost will vary from year to year. Half of the time in Waterloo you get a frost after April 15 so make sure that you are prepared to cover your pentas in the event of 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.