When to Plant Zinnia in Glendale, AZ

One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Glendale can be reviewed to determine when to plant zinnia.


Planting Calendar for Zinnia

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

Zinnia require warm weather which means that it's necessary to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

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 Glendale 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 zinnia and expect a good harvest is probably September. You probably don't want to wait any later than that or else your zinnia may not have a chance to really do well. If you are starting your zinnia indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Glendale. In the coldest months of winter you should expect an average low temperature of 25°F.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Glendale and it can change quite a bit from year to year. Since half of the time in Glendale there is a last frost after February 15 be ready to protect your zinnia if you have one of those late frosts.

USDA Zone Info for Glendale

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 Low25°F
Highest Expected Low30°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 Glendale

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