One of the first steps you take when you are estimating 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.

By using the USDA zone info for Napa you will be able to estimate when to plant bougainvillea.

Planting Calendar for Bougainvillea

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

It's a bad idea to plant bougainvillea until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant bougainvillea in Napa is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant bougainvillea and expect a good harvest is probably September. 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

On average the last frost when the weather gets warmer is on February 15 in Napa. It might get as low as 25°F during the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Napa and it can change quite a bit from year to year. Since half of the time in Napa it frosts late in the year after February 15 be ready to cover your bougainvillea if you have a surprise late frost.

USDA Zone Info for Napa

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°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 30°F.

Plants to Grow in Napa

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