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.

The USDA zone info for Princeton should be read to estimate when it's a good idea to plant ageratum.

Planting Calendar for Ageratum

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

You should not plant ageratum until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant ageratum in Princeton 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. You probably don't want to wait any later than that or else your ageratum may not have a chance to grow to maturity. 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 March 15 in Princeton. In the coldest months of winter you should expect an average low temperature of 10°F.

Since the USDA zone info for Princeton is an average the actual date of last frost changes from year to year. Half of the time in Princeton there is a last frost after March 15 so be sure to be ready to cover your ageratum if you have one of those late frosts.

USDA Zone Info for Princeton

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Princeton

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