One of the first steps you take when you are getting a good idea your gardening schedule is find your 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.

In Suisun City you can determine when it's possible to plant impatiens by reviewing the USDA zone info.

Planting Calendar for Impatiens

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

Since impatiens do not do well in cold weather it's important to wait until after the last frost before you can plant them.

The earliest that you can plant impatiens in Suisun City 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 impatiens and expect a good harvest is probably September. If you wait any later than that and your impatiens may not have a chance to grow to maturity. Starting your impatiens indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on February 15 in Suisun City. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Suisun City is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Suisun City you get surprised by a frost after February 15 so make sure that you are prepared to cover your impatiens if you have a late frost.

USDA Zone Info for Suisun City

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 Suisun City

You may be interested in your other planting guides for Suisun City.