One of the best tools that you have as gardeners to help us figure out 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.

A way of estimating when it's the best time to plant diascia is to consult the USDA zone info for Hillsboro.

Planting Calendar for Diascia

Frost tolerance for diascia:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Diascia can survive in moderate cold which tells us that you can plant them a little earlier in the year than other frost tender plants.

The earliest that you can plant diascia in Hillsboro is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant diascia and expect a good harvest is probably September. If you wait any later than that and your diascia may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your diascia indoors.

Last Frost Date

In Hillsboro the average date of last frost happens on March 15. It might get as low as 10°F during the coldest months of winter.

Keep in mind that USDA zone info for Hillsboro is just an average and the actual date of last frost will vary from year to year. Half of the time in Hillsboro you get surprised by a frost after March 15 so be sure to be ready to cover your diascia in the event of a late frost.

USDA Zone Info for Hillsboro

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Hillsboro

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