One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant bougainvillea in Watertown can be figured out by referring to the USDA zone info.

Planting Calendar for Bougainvillea

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

Since bougainvillea do not do well in cold weather it is important to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant bougainvillea in Watertown 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 fully mature. Starting your bougainvillea indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Watertown the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Keep in mind that USDA zone info for Watertown may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Watertown you get a frost after May 15 so be sure to be ready to protect your bougainvillea in the event of one of those late frosts.

USDA Zone Info for Watertown

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 Watertown

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