The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to figure out when it's possible to plant trifolium by using the USDA zone info for Waterville.

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 one of those plants that can tolerate a tiny bit of cold weather 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 trifolium in Waterville 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. You probably don't want to wait any later than that or else your trifolium may not have a chance to grow to maturity. If you are starting your trifolium indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Waterville the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -20°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 Waterville and it will vary from year to year. Since half of the time in Waterville last frost occurs after April 15 be ready to cover your trifolium if you have a late frost.

USDA Zone Info for Waterville

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Waterville

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