When to Plant Zinnia in Rosemead, CA

Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant zinnia in Rosemead should be determined by checking out the USDA zone info.


Planting Calendar for Zinnia

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

You really shouldn't plant zinnia until after the last frost because they are not cold tolerant.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant zinnia
Possibly ok, but a risky time to plant zinnia
Probably not a good time to plant zinnia

The earliest that you can plant zinnia in Rosemead 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 zinnia and expect a good harvest is probably September. Any later than that and your zinnia may not have a chance to really do well. Starting your zinnia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is January 31 in Rosemead. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for Rosemead may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Rosemead there is a last frost after January 31 so make sure that you are ready to protect your zinnia in the event of a surprise late frost.

USDA Zone Info for Rosemead

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)January 31
Average Date of First Frost (fall)December 15
Lowest Expected Low30°F
Highest Expected Low35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Rosemead

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