The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of determining when it's the best time to plant monarda is to check out the USDA zone info for Alton.

Planting Calendar for Monarda

Frost tolerance for monarda:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant monarda slightly earlier in the year because they are barely cold tolerant.

The earliest that you can plant monarda in Alton 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 monarda and expect a good harvest is probably August. If you wait any later than that and your monarda may not have a chance to really do well. Starting your monarda indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Alton. In the coldest months of winter you should expect an average low temperature of -10°F.

Since the USDA zone info for Alton is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Alton last frost occurs after April 15 so make sure that you are prepared to protect your monarda in the event of a surprise late frost.

USDA Zone Info for Alton

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 Alton

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