One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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 you should be able to determine when it's possible to plant clover.

Planting Calendar for Clover

Frost tolerance for clover:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Clover do ok in moderate cold which means that you can plant them slightly earlier than more sensitive plants.

The earliest that you can plant clover 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 clover and expect a good harvest is probably September. If you wait any later than that and your clover may not have a chance to really do well. You can get started a little bit earlier by starting your clover indoors.

Last Frost Date

The average date of last frost is February 15 in Portland. It might get as low as 25°F during the coldest months of winter.

Always keep in mind that USDA zone info for Portland is an average and the actual date of last frost will vary from year to year. Half of the time in Portland it frosts late in the year after February 15 so make sure that you are prepared to protect your clover in the event of one of those late frosts.

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.