One of the best tools that you have as gardeners to help us determine 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 looking at the USDA zone info for Beaverton it's a good idea to estimate when to plant tithonia.

Planting Calendar for Tithonia

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

It's probably not a good idea to plant tithonia until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant tithonia in Beaverton 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. You probably don't want to wait any later than that or else your tithonia may not have a chance to grow to maturity. Starting your tithonia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Beaverton is just an average the actual date of last frost changes from year to year. Since half of the time in Beaverton it frosts late in the year after March 15 be ready to cover your tithonia if you have a late frost.

USDA Zone Info for Beaverton

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 Beaverton

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