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

In South Haven you can determine when it's the best time to plant tree onions by using 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.

Since tree onions are one of those plants that can tolerate a tiny bit of cold weather you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant tree onions in South Haven 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. If you wait any later than that and 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 little bit earlier.

Last Frost Date

In South Haven the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -5°F.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for South Haven and it can change quite a bit from year to year. Half of the time in South Haven you get a frost after April 15 so be sure to be ready to protect your tree onions if you have a surprise late frost.

USDA Zone Info for South Haven

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in South Haven

You may be interested in your other planting guides for South Haven.