Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By using the USDA zone info for Corvallis it's possible to determine when you can plant catharanthus.

Planting Calendar for Catharanthus

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

Catharanthus do not do well in cold weather which means that you must wait until it warms up after the last frost before you can plant them.

The earliest that you can plant catharanthus in Corvallis 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. Any later than that and your catharanthus may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your catharanthus indoors.

Last Frost Date

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

Keep in mind that USDA zone info for Corvallis is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Corvallis you get a frost after March 15 so just be sure to be ready to cover your catharanthus in the event of one of those late frosts.

USDA Zone Info for Corvallis

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 Corvallis

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