One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant tithonia in Anchorage should be figured out by using the USDA zone info.

Planting Calendar for Tithonia

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

It's not a good idea to plant tithonia until after all chance of frost has passed because they require warm weather.

The earliest that you can plant tithonia in Anchorage is May. However, you really should wait until June 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 really do well. Starting your tithonia indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Anchorage. In the coldest months of winter you can expect an average low temperature of -25°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Anchorage and it is different every year. Half of the time in Anchorage there is a last frost after May 15 so make sure that you are prepared to cover your tithonia in the event of one of those late frosts.

USDA Zone Info for Anchorage

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Anchorage

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