The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant xerianthemum in Harvard should be determined by checking out the USDA zone info.

Planting Calendar for Xerianthemum

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

Xerianthemum can survive in some cold which means that you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant xerianthemum in Harvard 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 xerianthemum and expect a good harvest is probably August. If you wait any later than that and your xerianthemum may not have a chance to really do well. If you are starting your xerianthemum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Harvard. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Harvard is an average the actual date of last frost is different every year. Half of the time in Harvard you get a frost after April 15 so always be ready to protect your xerianthemum in the event of a late frost.

USDA Zone Info for Harvard

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°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 -10°F.

Plants to Grow in Harvard

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