Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's possible to determine when it's a good idea to plant nierembergia by referring to the USDA zone info for Hillsboro.

Planting Calendar for Nierembergia

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

It's not a good idea to plant nierembergia until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant nierembergia in Hillsboro 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 nierembergia and expect a good harvest is probably August. Any later than that and your nierembergia may not have a chance to grow to maturity. You can get started a little bit earlier by starting your nierembergia indoors.

Last Frost Date

In Hillsboro the average date of last frost happens on March 15. It might get as low as 15°F during the coldest months of winter.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Hillsboro and it changes from year to year. Since half of the time in Hillsboro you get a frost after March 15 be ready to cover your nierembergia if you have a surprise late frost.

USDA Zone Info for Hillsboro

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Hillsboro

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