One of the first steps you take when you are getting a good idea 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.

By using the USDA zone info for Sterling you should be able to determine when to plant pentas.

Planting Calendar for Pentas

Frost tolerance for pentas:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

You really shouldn't plant pentas until after the last frost has passed because they do not do well in cold weather.

The earliest that you can plant pentas in Sterling 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. Any later than that and your pentas may not have a chance to grow to maturity. If you are starting your pentas indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Sterling and it changes from year to year. Half of the time in Sterling you get surprised by 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 Sterling

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 Sterling

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