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.

You should be able to determine when it's a good idea to plant argyranthemum by using the USDA zone info for Colusa.

Planting Calendar for Argyranthemum

Frost tolerance for argyranthemum:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Argyranthemum require warm weather which tells us that it's necessary to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant argyranthemum in Colusa 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 argyranthemum and expect a good harvest is probably September. Any later than that and your argyranthemum may not have a chance to really do well. You can get started a few weeks earlier by starting your argyranthemum indoors.

Last Frost Date

In Colusa the average date of last frost happens on February 15. In the coldest months of winter you should expect an average low temperature of 25°F.

Remember that USDA zone info for Colusa is not always accurate and the actual date of last frost is different every year. Half of the time in Colusa you get surprised by a frost after February 15 so just be sure to be ready to protect your argyranthemum if you have a surprise late frost.

USDA Zone Info for Colusa

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Colusa

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