One of the first steps you take when you are making a decision about your gardening schedule is find your 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.

The earliest that you can plant zinnia in Madison should be estimated by looking at the USDA zone info.

Planting Calendar for Zinnia

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

It's probably a bad idea to plant zinnia until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant zinnia in Madison 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. Any later than that and 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 little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Madison. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for Madison is not always accurate the actual date of last frost will vary from year to year. Half of the time in Madison you get a frost after April 15 so make sure that you are ready to cover your zinnia if you have a late frost.

USDA Zone Info for Madison

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 Madison

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