One of the first steps you take when you are making a decision about your gardening schedule is find your 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 USDA zone info for Westfield should be looked at to figure out when it's a good idea to plant onions.

Planting Calendar for Onions

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

Since onions are very cold tolerant you can plant them earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant onions in Westfield 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 onions and expect a good harvest is probably September. Any later than that and your onions may not have a chance to grow to maturity. If you are starting your onions indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Westfield. In the coldest months of winter you should expect an average low temperature of -15°F.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Westfield and it will vary from year to year. Since half of the time in Westfield you get a frost after April 15 be ready to protect your onions if you have a surprise late frost.

USDA Zone Info for Westfield

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 Westfield

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