One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By using the USDA zone info for Portland it's a good idea to figure out when it's the best time to plant garden mums.

Planting Calendar for Garden Mums

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

Since garden mums are moderately cold tolerant you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant garden mums in Portland 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 garden mums and expect a good harvest is probably September. Any later than that and your garden mums may not have a chance to really do well. You can get started a couple of weeks earlier by starting your garden mums indoors.

Last Frost Date

The average date of last frost is March 15 in Portland. In the coldest months of winter you can expect an average low temperature of 15°F.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Portland and it is different every year. Half of the time in Portland last frost occurs after March 15 so be sure to be ready to cover your garden mums 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.