One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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.

A common way of making a decision about when it's a good idea to plant dahlia is to use the USDA zone info for Manteca.

Planting Calendar for Dahlia

Frost tolerance for dahlia:	Not tolerant of frost.
When to plant:	After the last frost.

Dahlia do not do well in cold weather which means that you must wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant dahlia in Manteca 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 dahlia and expect a good harvest is probably September. You probably don't want to wait any later than that or else your dahlia may not have a chance to fully mature. Starting your dahlia 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. In the coldest months of winter you should expect an average low temperature of 25°F.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Manteca and it changes from year to year. Since half of the time in Manteca there is a last frost after February 15 be ready to protect your dahlia in the event of one of those late frosts.

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.