One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Snohomish you should be able to figure out when to plant argyranthemum.

Planting Calendar for Argyranthemum

Frost tolerance for argyranthemum:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Argyranthemum do not do well in cold weather which tells us that you need to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant argyranthemum in Snohomish is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant argyranthemum and expect a good harvest is probably August. You probably don't want to wait any later than that or else your argyranthemum may not have a chance to grow to maturity. If you are starting your argyranthemum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost has passed is on March 15 in Snohomish. In the coldest months of winter you should expect an average low temperature of 15°F.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Snohomish and it is different every year. Half of the time in Snohomish you get a frost after March 15 so always be ready to cover your argyranthemum if you have one of those late frosts.

USDA Zone Info for Snohomish

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Snohomish

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