One of the first steps you take when you are determining your gardening schedule is find your 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 common way of getting a good idea when it's possible to plant helianthemum is to consult the USDA zone info for Punxsutawney.

Planting Calendar for Helianthemum

Frost tolerance for helianthemum:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Helianthemum do ok in some cold which means that you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant helianthemum in Punxsutawney is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant helianthemum and expect a good harvest is probably September. You probably don't want to wait any later than that or else your helianthemum may not have a chance to really do well. Starting your helianthemum indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Always keep in mind that USDA zone info for Punxsutawney is just an average and the actual date of last frost will vary from year to year. Since half of the time in Punxsutawney it frosts late in the year after April 15 be ready to protect your helianthemum if you have one of those late frosts.

USDA Zone Info for Punxsutawney

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 Punxsutawney

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