Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Rosenberg you can determine when to plant tree onions by checking out 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 are barely cold tolerant which means that you can start planting them slightly earlier than other plants that might not handle the cold.

The earliest that you can plant tree onions in Rosenberg 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 tree onions and expect a good harvest is probably September. If you wait any later than that and your tree onions may not have a chance to really do well. You can get started a little bit earlier by starting your tree onions indoors.

Last Frost Date

The average date of last frost is February 15 in Rosenberg. In the coldest months of winter you can expect an average low temperature of 20°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Rosenberg and it is different every year. Half of the time in Rosenberg it frosts late in the year after February 15 so be sure to be ready to cover your tree onions if you have one of those late frosts.

USDA Zone Info for Rosenberg

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

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

Plants to Grow in Rosenberg

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