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 Suffolk you can determine when it's possible to plant tree onions by referring to the USDA zone info.

Planting Calendar for Tree onions

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

Tree onions do ok in mild cold which tells us that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant tree onions in Suffolk 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 tree onions and expect a good harvest is probably August. You probably don't want to wait any later than that or else your tree onions may not have a chance to fully mature. Starting your tree onions indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost is on March 15 in Suffolk. In the coldest months of winter you should expect an average low temperature of 10°F.

Since the USDA zone info for Suffolk is just an average the actual date of last frost changes from year to year. Since half of the time in Suffolk you get a frost after March 15 be ready to cover your tree onions if you have one of those late frosts.

USDA Zone Info for Suffolk

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Suffolk

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