One of the first steps you take when you are determining 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.

In Washington you can figure out when you can plant lisianthus by looking at 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 are not cold tolerant it is necessary to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant lisianthus in Washington 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. If you wait any later than that and your lisianthus may not have a chance to really do well. If you are starting your lisianthus indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Washington the average date of last frost happens on March 15. You can expect an average low temperature of 10°F in the coldest months of winter.

Remember that USDA zone info for Washington may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Washington you get a frost after March 15 be ready to protect your lisianthus in the event of a surprise late frost.

USDA Zone Info for Washington

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 Washington

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