Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to figure out when it's the best time to plant catharanthus by checking 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 when the weather gets warmer.

Since catharanthus require warm weather you really should wait until after the last 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. You probably don't want to wait any later than that or else your catharanthus may not have a chance to grow to maturity. Starting your catharanthus indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Madison. In the coldest months of winter you should expect an average low temperature of 5°F.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Madison and it changes from year to year. Half of the time in Madison last frost occurs after April 15 so be sure to be ready to cover your catharanthus if you have a surprise late frost.

USDA Zone Info for Madison

Here is the info for USDA Zone 7b.

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

Plants to Grow in Madison

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