One of the first steps you take when you are getting a good idea 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.

In West Linn you can figure out when it's possible to plant catharanthus by using the USDA zone info.

Planting Calendar for Catharanthus

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

Since catharanthus do not do well in cold weather you need to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant catharanthus in West Linn 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 grow to maturity. If you are starting your catharanthus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In West Linn the average date of last frost happens on March 15. In the coldest months of winter you can expect an average low temperature of 15°F.

Always keep in mind that USDA zone info for West Linn may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in West Linn last frost occurs after March 15 so just be sure to be ready to cover your catharanthus if you have a late frost.

USDA Zone Info for West Linn

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 West Linn

You may be interested in your other planting guides for West Linn.