One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

A way of figuring out when you can plant tree onions is to consult the USDA zone info for Key Biscayne.

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 plants that are more sensitive to the cold.

The earliest that you can plant tree onions in Key Biscayne is January. However, you really should wait until February 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 November. If you wait any later than that and your tree onions may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your tree onions indoors.

Last Frost Date

In Key Biscayne it never frosts. In the coldest months of winter you can expect an average low temperature of 40°F.

Since the USDA zone info for Key Biscayne is just an average the actual date of last frost will vary from year to year. Since it never frosts in Key Biscayne you do not have to be ready to protect your tree onions if you have a late frost.

USDA Zone Info for Key Biscayne

Here is the info for USDA Zone 11a.

Average Date of Last Frost (spring)	Never
Average Date of First Frost (fall)	Never
Lowest Expected Low	40°F
Highest Expected Low	45°F

This means that on a really cold year, the coldest it will get is 40°F. On most years you should be prepared to experience lows near 45°F.

Plants to Grow in Key Biscayne

You may be interested in your other planting guides for Key Biscayne.