One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

You should be able to estimate when it's a good idea to plant oleander by looking at the USDA zone info for Marengo.

Planting Calendar for Oleander

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

Since oleander are not cold tolerant you need to wait until after the last frost has passed before you can plant them.

The earliest that you can plant oleander in Marengo 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 oleander and expect a good harvest is probably August. You probably don't want to wait any later than that or else your oleander may not have a chance to really do well. You can get started a little bit earlier by starting your oleander indoors.

Last Frost Date

The average date of last frost is April 15 in Marengo. In the coldest months of winter you should expect an average low temperature of -15°F.

It's important to 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 Marengo and it changes from year to year. Since half of the time in Marengo there is a last frost after April 15 be ready to cover your oleander in the event of one of those late frosts.

USDA Zone Info for Marengo

Here is the info for USDA Zone 5b.

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

Plants to Grow in Marengo

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