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.

In Trenton you can determine when you can plant calendula by checking out the USDA zone info.

Planting Calendar for Calendula

Frost tolerance for calendula:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Calendula tend to make it in some cold which tells us that you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant calendula in Trenton is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant calendula and expect a good harvest is probably September. If you wait any later than that and your calendula may not have a chance to grow to maturity. Starting your calendula indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Trenton the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 0°F.

Always keep in mind that USDA zone info for Trenton is an average and the actual date of last frost is different every year. Since half of the time in Trenton there is a last frost after April 15 be ready to protect your calendula if you have a late frost.

USDA Zone Info for Trenton

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Trenton

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