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.

A common way of determining when it's possible to plant diascia is to examine the USDA zone info for Lake Oswego.

Planting Calendar for Diascia

Frost tolerance for diascia:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant diascia a little earlier in the year because they do well in moderate cold.

The earliest that you can plant diascia in Lake Oswego is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant diascia and expect a good harvest is probably September. Any later than that and your diascia may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your diascia indoors.

Last Frost Date

On average the last frost has passed is on March 15 in Lake Oswego. In the coldest months of winter you can expect an average low temperature of 15°F.

Keep in mind that USDA zone info for Lake Oswego is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Lake Oswego there is a last frost after March 15 so be sure to be ready to protect your diascia in the event of a surprise late frost.

USDA Zone Info for Lake Oswego

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 Lake Oswego

You may be interested in your other planting guides for Lake Oswego.