Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant delphinium in Manteca should be determined by referring to 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 can survive in some cold which tells us that you can plant them just a tiny bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant delphinium in Manteca 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. You probably don't want to wait any later than that or else your delphinium may not have a chance to fully mature. Starting your delphinium indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Manteca the average date of last frost happens on February 15. You should expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Manteca is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Manteca you get surprised by a frost after February 15 so make sure that you are ready to protect your delphinium if you have a surprise late frost.

USDA Zone Info for Manteca

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 Manteca

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