One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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.

A common way of determining when to plant regal geranium is to examine the USDA zone info for Waukesha.

Planting Calendar for Regal Geranium

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

Regal Geranium tend to make it in a tiny bit of cold which tells us that you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant regal geranium in Waukesha 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 regal geranium and expect a good harvest is probably August. You probably don't want to wait any later than that or else your regal geranium may not have a chance to really do well. You can get started a few weeks earlier by starting your regal geranium indoors.

Last Frost Date

The average date of last frost is April 15 in Waukesha. It might get as low as -15°F during the coldest months of winter.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Waukesha and it changes from year to year. Since half of the time in Waukesha you get a frost after April 15 be ready to cover your regal geranium in the event of one of those late frosts.

USDA Zone Info for Waukesha

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 Waukesha

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