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.

In Ukiah you can determine when you can plant ageratum by reviewing the USDA zone info.

Planting Calendar for Ageratum

Frost tolerance for ageratum:	Not tolerant of frost.
When to plant:	After the last frost.

Since ageratum do not do well in cold weather you must wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant ageratum in Ukiah 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 ageratum and expect a good harvest is probably September. You probably don't want to wait any later than that or else your ageratum may not have a chance to fully mature. If you are starting your ageratum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Ukiah the average date of last frost happens on February 15. It might get as low as 20°F during the coldest months of winter.

Since the USDA zone info for Ukiah 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 Ukiah it frosts late in the year after February 15 so always be ready to protect your ageratum in the event of a surprise late frost.

USDA Zone Info for Ukiah

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 Ukiah

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