One of the first steps you take when you are estimating 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.

The USDA zone info for Portland should be reviewed to figure out when it's the best time 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 very little cold which tells us that you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant clover 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 clover and expect a good harvest is probably August. You probably don't want to wait any later than that or else your clover may not have a chance to fully mature. If you are starting your clover indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Portland the average date of last frost happens on March 15. You should expect an average low temperature of 15°F in the coldest months of winter.

It's important to remember that USDA zone info for Portland is an average and the actual date of last frost is different every year. Half of the time in Portland there is a last frost after March 15 so make sure that you are ready to cover your clover in the event of one of those late frosts.

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.