One of the best tools that you have as gardeners to help us estimate 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 referring to the USDA zone info for Prosser you should be able to figure out when it's a good idea to plant echinacea.

Planting Calendar for Echinacea

Frost tolerance for echinacea:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Echinacea can survive in a tiny bit of cold which tells us that you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant echinacea in Prosser 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 echinacea and expect a good harvest is probably August. You probably don't want to wait any later than that or else your echinacea may not have a chance to fully mature. You can get started a few weeks earlier by starting your echinacea indoors.

Last Frost Date

The average date of last frost is April 15 in Prosser. It might get as low as 0°F during the coldest months of winter.

Remember that USDA zone info for Prosser is an average and the actual date of last frost is different every year. Since half of the time in Prosser you get a frost after April 15 be ready to protect your echinacea if you have one of those late frosts.

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.