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.

The first opportunity to plant argyranthemum in Prosser should be determined by reviewing the USDA zone info.

Planting Calendar for Argyranthemum

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

Since argyranthemum require warm weather it's important to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant argyranthemum in Prosser 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. If you wait any later than that and your argyranthemum may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your argyranthemum indoors.

Last Frost Date

In Prosser the average date of last frost happens on April 15. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Prosser is not always accurate the actual date of last frost will vary from year to year. Half of the time in Prosser it frosts late in the year after April 15 so always be ready to cover your argyranthemum if you have a surprise late frost.

USDA Zone Info for Prosser

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Prosser

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