Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of estimating when it's a good idea to plant helianthemum is to examine the USDA zone info for Rochester.

Planting Calendar for Helianthemum

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

Helianthemum do well in moderate cold which means that you can plant them earlier than plants that are more sensitive to the cold.

The earliest that you can plant helianthemum in Rochester 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. Any later than that and your helianthemum may not have a chance to fully mature. If you are starting your helianthemum indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Rochester. In the coldest months of winter you can expect an average low temperature of -10°F.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Rochester and it changes from year to year. Since half of the time in Rochester last frost occurs after April 15 be ready to cover your helianthemum if you have a late frost.

USDA Zone Info for Rochester

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Rochester

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