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.

A way of estimating when to plant catharanthus is to check out the USDA zone info for Madison.

Planting Calendar for Catharanthus

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

Catharanthus require warm weather which tells us that it is important to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant catharanthus 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 catharanthus and expect a good harvest is probably August. Any later than that and your catharanthus may not have a chance to fully mature. You can get started a few weeks earlier by starting your catharanthus indoors.

Last Frost Date

The average date of last frost is April 15 in Madison. In the coldest months of winter you can expect an average low temperature of -5°F.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Madison and it is different every year. Half of the time in Madison you get a frost after April 15 so make sure that you are prepared to protect your catharanthus in the event of a surprise 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.