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

The best time to plant helianthemum in Palmyra should be figured out by referring to the USDA zone info.

Planting Calendar for Helianthemum

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

You can plant helianthemum a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant helianthemum in Palmyra 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. If you wait 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 couple of weeks earlier.

Last Frost Date

In Palmyra the average date of last frost happens on April 15. You should expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Palmyra is an average the actual date of last frost changes from year to year. Half of the time in Palmyra there is a last frost after April 15 so always be ready to protect your helianthemum in the event of a surprise late frost.

USDA Zone Info for Palmyra

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Palmyra

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