One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Ogdensburg should be reffered to in order to figure out when you can plant helianthemum.

Planting Calendar for Helianthemum

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

Helianthemum are one of those plants that can tolerate a little bit of cold weather which means that you can get them planted earlier than other plants that might not handle the cold.

The earliest that you can plant helianthemum in Ogdensburg 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 helianthemum and expect a good harvest is probably August. You probably don't want to wait any later than that or else your helianthemum may not have a chance to grow to maturity. If you are starting your helianthemum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost has passed is on May 15 in Ogdensburg. It might get as low as -25°F during the coldest months of winter.

It's important to remember that USDA zone info for Ogdensburg is an average and the actual date of last frost changes from year to year. Since half of the time in Ogdensburg there is a last frost after May 15 be ready to cover your helianthemum in the event of a surprise late frost.

USDA Zone Info for Ogdensburg

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Ogdensburg

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