The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. 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 getting a good idea when to plant yarrow is to use the USDA zone info for Rosenberg.

Planting Calendar for Yarrow

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

Yarrow tend to make it in quite a bit of cold which tells us 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 yarrow in Rosenberg 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 yarrow and expect a good harvest is probably October. You probably don't want to wait any later than that or else your yarrow may not have a chance to grow to maturity. If you are starting your yarrow indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Rosenberg the average date of last frost happens on February 15. You should expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Rosenberg may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Rosenberg last frost occurs after February 15 so make sure that you are ready to protect your yarrow 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.