The USDA Zone info is a great tool for gardeners to help us figure out 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.

You should be able to figure out when to plant dahlia by looking at the USDA zone info for Marathon.

Planting Calendar for Dahlia

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

Dahlia do not do well in cold weather which tells us that you really should wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant dahlia in Marathon is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant dahlia and expect a good harvest is probably November. You probably don't want to wait any later than that or else your dahlia may not have a chance to fully mature. Starting your dahlia indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Marathon it never frosts. It might get as low as 45°F during the coldest months of winter.

Remember that USDA zone info for Marathon is just an average and the actual date of last frost will vary from year to year. Since it never frosts in Marathon you do not have to be ready to cover your dahlia if you have a surprise late frost.

USDA Zone Info for Marathon

Here is the info for USDA Zone 11b.

Average Date of Last Frost (spring)	Never
Average Date of First Frost (fall)	Never
Lowest Expected Low	45°F
Highest Expected Low	50°F

This means that on a really cold year, the coldest it will get is 45°F. On most years you should be prepared to experience lows near 50°F.

Plants to Grow in Marathon

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