One of the first steps you take when you are figuring out 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.

It's a good idea to figure out when you can plant sweet sultan by checking out the USDA zone info for Waterloo.

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 some cold which means that you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant sweet sultan in Waterloo 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. If you wait any later than that and your sweet sultan may not have a chance to really do well. You can get started a little bit earlier by starting your sweet sultan indoors.

Last Frost Date

In Waterloo the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for Waterloo is an average the actual date of last frost changes from year to year. Half of the time in Waterloo 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 Waterloo

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 Waterloo

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