Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of getting a good idea when to plant trachelium is to use the USDA zone info for Belfast.

Planting Calendar for Trachelium

Frost tolerance for trachelium:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Trachelium require warm weather which tells us that it's necessary to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

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

Last Frost Date

On average the last frost has passed is on April 15 in Belfast. You should expect an average low temperature of -15°F in the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Belfast and it will vary from year to year. Since half of the time in Belfast it frosts late in the year after April 15 be ready to protect your trachelium in the event of a surprise late frost.

USDA Zone Info for Belfast

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 Belfast

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