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.

The earliest that you can plant delphinium in Roseville can be estimated by checking out the USDA zone info.

Planting Calendar for Delphinium

Frost tolerance for delphinium:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Delphinium do ok in very little cold which means that you can plant them just a tiny bit earlier in the year than other frost tender plants.

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

The last month that you can plant delphinium and expect a good harvest is probably September. If you wait any later than that and your delphinium may not have a chance to fully mature. You can get started a little bit earlier by starting your delphinium indoors.

Last Frost Date

On average the last frost has passed is on February 15 in Roseville. You can expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Roseville is just an average the actual date of last frost is different every year. Since half of the time in Roseville it frosts late in the year after February 15 be ready to cover your delphinium in the event of a surprise late frost.

USDA Zone Info for Roseville

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 Roseville

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