One of the first steps you take when you are estimating 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.

You will be able to estimate when it's a good idea to plant cardinal flower by referring to the USDA zone info for Trenton.

Planting Calendar for Cardinal Flower

Frost tolerance for cardinal flower:	Not tolerant of frost.
When to plant:	After the last frost has passed.

It's a bad idea to plant cardinal flower until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant cardinal flower in Trenton 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 cardinal flower and expect a good harvest is probably August. You probably don't want to wait any later than that or else your cardinal flower may not have a chance to grow to maturity. Starting your cardinal flower indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Trenton and it changes from year to year. Since half of the time in Trenton it frosts late in the year after April 15 be ready to protect your cardinal flower in the event of a surprise late frost.

USDA Zone Info for Trenton

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 Trenton

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