Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of making a decision about when to plant marigold is to check out the USDA zone info for Rock Springs.

Planting Calendar for Marigold

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

Since marigold do not do well in cold weather you have to wait until after the last frost before you can plant them.

The earliest that you can plant marigold in Rock Springs 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. 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 few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Rock Springs. You can expect an average low temperature of -20°F in the coldest months of winter.

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 Rock Springs and it will vary from year to year. Since half of the time in Rock Springs last frost occurs after April 15 be ready to cover your marigold in the event of a surprise late frost.

USDA Zone Info for Rock Springs

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Rock Springs

You may be interested in your other planting guides for Rock Springs.