When to Plant Calliopsis in Hillsboro, OR

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.

The first opportunity to plant calliopsis in Hillsboro can be estimated by using the USDA zone info.


Planting Calendar for Calliopsis

Frost tolerance for calliopsis: Not tolerant of frost.
When to plant: After the last frost has passed.

Since calliopsis require warm weather it's important to wait until after the last frost has passed before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant calliopsis
Possibly ok, but a risky time to plant calliopsis
Probably not a good time to plant calliopsis

The earliest that you can plant calliopsis 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 calliopsis and expect a good harvest is probably August. You probably don't want to wait any later than that or else your calliopsis may not have a chance to really do well. You can get started a couple of weeks earlier by starting your calliopsis indoors.

Last Frost Date

On average the last frost has passed is on March 15 in Hillsboro. It might get as low as 15°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Hillsboro and it is different every year. Half of the time in Hillsboro it frosts late in the year after March 15 so just be sure to be ready to cover your calliopsis 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 Low15°F
Highest Expected Low20°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.