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.

The USDA zone info for Ketchikan can be reffered to in order to estimate when you can plant tithonia.

Planting Calendar for Tithonia

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

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

The earliest that you can plant tithonia in Ketchikan 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

The average date of last frost is April 15 in Ketchikan. It might get as low as 5°F during the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Ketchikan and it will vary from year to year. Since half of the time in Ketchikan there is a last frost after April 15 be ready to protect your tithonia in the event of one of those late frosts.

USDA Zone Info for Ketchikan

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Ketchikan

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