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.

It's a good idea to estimate when to plant marigold by using the USDA zone info for Berwyn.

Planting Calendar for Marigold

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

Since marigold are not cold tolerant it is necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant marigold in Berwyn 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 marigold and expect a good harvest is probably August. If you wait any later than that and your marigold may not have a chance to grow to maturity. Starting your marigold indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Berwyn the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -10°F.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Berwyn and it will vary from year to year. Since half of the time in Berwyn you get surprised by a frost after April 15 be ready to protect your marigold if you have one of those late frosts.

USDA Zone Info for Berwyn

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Berwyn

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