Before planting it is a good idea to find your USDA Zone info to figure out 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.

By checking out the USDA zone info for Decorah you should be able to determine when it's a good idea to plant bougainvillea.

Planting Calendar for Bougainvillea

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

You really shouldn't plant bougainvillea until after the last frost has passed because they require warm weather.

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

Last Frost Date

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

Since the USDA zone info for Decorah is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Decorah last frost occurs after May 15 be ready to cover your bougainvillea in the event of one of those late frosts.

USDA Zone Info for Decorah

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 Decorah

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