Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can determine when it's possible to plant lisianthus in Oregon by referring to the USDA zone info.

Planting Calendar for Lisianthus

Frost tolerance for lisianthus:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since lisianthus require warm weather you really should wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant lisianthus in Oregon 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 lisianthus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your lisianthus may not have a chance to grow to maturity. Starting your lisianthus indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Oregon the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -20°F.

Since the USDA zone info for Oregon may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Oregon you get a frost after April 15 so make sure that you are ready to protect your lisianthus in the event of a surprise late frost.

USDA Zone Info for Oregon

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 Oregon

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