Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Harvard you can determine when you can plant sweet sultan by looking at the USDA zone info.

Planting Calendar for Sweet Sultan

Frost tolerance for sweet sultan:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Sweet Sultan do ok in moderate cold which tells us that you can plant them slightly earlier than plants that are more sensitive to the cold.

The earliest that you can plant sweet sultan in Harvard 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 sweet sultan and expect a good harvest is probably August. Any later than that and your sweet sultan may not have a chance to really do well. Starting your sweet sultan indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Harvard. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Harvard is an average the actual date of last frost changes from year to year. Half of the time in Harvard there is a last frost after April 15 so make sure that you are prepared to protect your sweet sultan in the event of one of those late frosts.

USDA Zone Info for Harvard

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 Harvard

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