The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Belfast you should be able to figure out when you can plant sweet peas.

Planting Calendar for Sweet Peas

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

Sweet Peas tend to make it in very little cold which tells us that you can plant them just a tiny bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant sweet peas 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 sweet peas and expect a good harvest is probably August. If you wait any later than that and your sweet peas may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your sweet peas indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Belfast. In the coldest months of winter you can expect an average low temperature of -15°F.

Keep in mind that USDA zone info for Belfast is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Belfast last frost occurs after April 15 be ready to protect your sweet peas if you have a 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.