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.

A way of estimating when it's the best time to plant xerianthemum is to consult the USDA zone info for Belfast.

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.

Since xerianthemum are barely cold tolerant you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant xerianthemum in Belfast 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. Any later than that and your xerianthemum may not have a chance to really do well. Starting your xerianthemum indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Belfast the average date of last frost happens on April 15. You can expect an average low temperature of -15°F in the coldest months of winter.

Remember that USDA zone info for Belfast may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Belfast last frost occurs after April 15 so make sure that you are ready to cover your xerianthemum in the event of a surprise late frost.

USDA Zone Info for Belfast

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 Belfast

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