One of the first steps you take when you are estimating 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.

It's possible to determine when you can plant onions by reviewing the USDA zone info for Berlin.

Planting Calendar for Onions

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

Onions can survive in pretty solid cold which means that you can plant them much earlier in the year than other plants that might not handle the cold.

The earliest that you can plant onions in Berlin 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 onions and expect a good harvest is probably August. If you wait any later than that and your onions may not have a chance to fully mature. If you are starting your onions indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Berlin. You should expect an average low temperature of -25°F in the coldest months of winter.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Berlin and it can change quite a bit from year to year. Half of the time in Berlin it frosts late in the year after May 15 so make sure that you are prepared to protect your onions if you have a surprise late frost.

USDA Zone Info for Berlin

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Berlin

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