One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can determine when it's a good idea to plant catharanthus in Chehalis by referring to the USDA zone info.

Planting Calendar for Catharanthus

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

Since catharanthus do not do well in cold weather you must wait until after the last frost before you can plant them.

The earliest that you can plant catharanthus in Chehalis 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 catharanthus and expect a good harvest is probably August. If you wait any later than that and your catharanthus may not have a chance to fully mature. Starting your catharanthus indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Chehalis. You can expect an average low temperature of 10°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Chehalis may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Chehalis you get a frost after March 15 so just be sure to be ready to protect your catharanthus if you have one of those late frosts.

USDA Zone Info for Chehalis

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Chehalis

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