Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. 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 coleus in Marshalltown should be estimated by referring to the USDA zone info.

Planting Calendar for Coleus

Frost tolerance for coleus:	Not tolerant of frost.
When to plant:	After the last frost.

It's a bad idea to plant coleus until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant coleus in Marshalltown 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 coleus and expect a good harvest is probably August. Any later than that and your coleus may not have a chance to fully mature. If you are starting your coleus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Marshalltown the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -20°F.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Marshalltown and it will vary from year to year. Since half of the time in Marshalltown it frosts late in the year after April 15 be ready to cover your coleus if you have a late frost.

USDA Zone Info for Marshalltown

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Marshalltown

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