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

In Belfast you can estimate when it's a good idea to plant radishes by using the USDA zone info.

Planting Calendar for Radishes

Frost tolerance for radishes:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Radishes can survive in cold weather which tells us that you can plant them much earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant radishes in Belfast 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 radishes and expect a good harvest is probably September. You probably don't want to wait any later than that or else your radishes may not have a chance to really do well. You can get started a few weeks earlier by starting your radishes indoors.

Last Frost Date

In Belfast the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Belfast is just an average the actual date of last frost will vary from year to year. Half of the time in Belfast you get surprised by a frost after April 15 so make sure that you are ready to cover your radishes 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.