The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for West Linn can be read to figure out when to plant tithonia.

Planting Calendar for Tithonia

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

It's probably not a good idea to plant tithonia until after the last frost because they do not do well in cold weather.

The earliest that you can plant tithonia 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 tithonia and expect a good harvest is probably August. Any later than that and your tithonia may not have a chance to grow to maturity. If you are starting your tithonia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is March 15 in West Linn. It might get as low as 15°F during the coldest months of winter.

Since the USDA zone info for West Linn is just an average the actual date of last frost changes from year to year. Half of the time in West Linn you get a frost after March 15 so be sure to be ready to cover your tithonia if you have a surprise 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.