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.

The best time to plant trifolium in Oregon City should be figured out by looking at the USDA zone info.

Planting Calendar for Trifolium

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

You can plant trifolium a bit earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant trifolium in Oregon City 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 trifolium and expect a good harvest is probably August. If you wait any later than that and your trifolium may not have a chance to fully mature. If you are starting your trifolium indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

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

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Oregon City and it will vary from year to year. Since half of the time in Oregon City there is a last frost after March 15 be ready to cover your trifolium in the event of a late frost.

USDA Zone Info for Oregon City

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 Oregon City

You may be interested in your other planting guides for Oregon City.