One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when to plant trifolium in Snohomish 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.

Since trifolium are barely cold tolerant you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant trifolium in Snohomish 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. Any later than that and your trifolium may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your trifolium indoors.

Last Frost Date

In Snohomish 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.

Since the USDA zone info for Snohomish may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Snohomish it frosts late in the year after March 15 so always be ready to protect your trifolium in the event of a surprise late frost.

USDA Zone Info for Snohomish

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 Snohomish

You may be interested in your other planting guides for Snohomish.