One of the best tools that you have as gardeners to help us determine 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 way of making a decision about when to plant ageratum is to consult the USDA zone info for Norfolk.

Planting Calendar for Ageratum

Frost tolerance for ageratum:	Not tolerant of frost.
When to plant:	After the last frost.

Ageratum require warm weather which means that it is important to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant ageratum in Norfolk is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant ageratum and expect a good harvest is probably August. If you wait any later than that and your ageratum may not have a chance to fully mature. If you are starting your ageratum indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Norfolk. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Norfolk is an average the actual date of last frost is different every year. Half of the time in Norfolk last frost occurs after April 15 so make sure that you are ready to protect your ageratum in the event of one of those late frosts.

USDA Zone Info for Norfolk

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Norfolk

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