One of the best tools that you have as gardeners to help us estimate 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 first chance to plant celery in Belfast should be determined by using the USDA zone info.

Planting Calendar for Celery

Frost tolerance for celery:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Celery are one of those plants that can tolerate a tiny bit of cold weather which means that you can plant them slightly earlier than more sensitive plants.

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

The last month that you can plant celery and expect a good harvest is probably August. You probably don't want to wait any later than that or else your celery may not have a chance to fully mature. If you are starting your celery indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

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

Since the USDA zone info for Belfast may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Belfast you get surprised by a frost after April 15 be ready to protect your celery if you have one of those late frosts.

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.