Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant schizanthus in Portland can be determined by looking at the USDA zone info.

Planting Calendar for Schizanthus

Frost tolerance for schizanthus:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Schizanthus are not cold tolerant which tells us that it is necessary to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

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

Last Frost Date

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

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

USDA Zone Info for Portland

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 Low	15°F
Highest Expected Low	20°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 Portland

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