Before planting it is a good idea to find your USDA Zone info to estimate 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.

By checking out the USDA zone info for Mendham it's possible to estimate when it's the best time to plant zinnia.

Planting Calendar for Zinnia

Frost tolerance for zinnia:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's not a good idea to plant zinnia until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant zinnia in Mendham is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant zinnia and expect a good harvest is probably August. You probably don't want to wait any later than that or else your zinnia may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your zinnia indoors.

Last Frost Date

In Mendham the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -5°F.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Mendham and it is different every year. Since half of the time in Mendham there is a last frost after April 15 be ready to protect your zinnia in the event of one of those late frosts.

USDA Zone Info for Mendham

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Mendham

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