The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of figuring out when it's a good idea to plant asparagus is to use the USDA zone info for Portland.

Planting Calendar for Asparagus

Frost tolerance for asparagus:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

You can plant asparagus a lot earlier in the year because they do well in cold.

The earliest that you can plant asparagus in Portland is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant asparagus and expect a good harvest is probably October. Any later than that and your asparagus may not have a chance to fully mature. Starting your asparagus indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Portland. In the coldest months of winter you can expect an average low temperature of 25°F.

Remember that USDA zone info for Portland may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Portland there is a last frost after February 15 so make sure that you are prepared to protect your asparagus if you have 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.