When to Plant Heliotrope in Hillsboro, OR

The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant heliotrope in Hillsboro should be determined by reviewing the USDA zone info.


Planting Calendar for Heliotrope

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

It's probably a bad idea to plant heliotrope until after all chance of frost has passed because they do not do well in cold weather.

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

The earliest that you can plant heliotrope 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 heliotrope and expect a good harvest is probably August. Any later than that and your heliotrope may not have a chance to really do well. If you are starting your heliotrope indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost is on March 15 in Hillsboro. You should expect an average low temperature of 15°F in the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Hillsboro and it changes from year to year. Half of the time in Hillsboro it frosts late in the year after March 15 so just be sure to be ready to protect your heliotrope if you have one of those late frosts.

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.