One of the first steps you take when you are making a decision about 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.

You should be able to determine when it's the best time to plant polka dot plant by looking at the USDA zone info for Portland.

Planting Calendar for Polka Dot Plant

Frost tolerance for polka dot plant:	Not tolerant of frost.
When to plant:	After the last frost.

It's a bad idea to plant polka dot plant until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant polka dot plant in Portland is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant polka dot plant and expect a good harvest is probably September. If you wait any later than that and your polka dot plant may not have a chance to really do well. You can get started a couple of weeks earlier by starting your polka dot plant indoors.

Last Frost Date

On average all chance of frost has passed is on February 15 in Portland. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Portland is not always accurate the actual date of last frost is different every year. Half of the time in Portland there is a last frost after February 15 so make sure that you are ready to protect your polka dot plant in the event of a surprise late frost.

USDA Zone Info for Portland

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Portland

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