One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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.

You can estimate when to plant catharanthus in Madison by looking at the USDA zone info.

Planting Calendar for Catharanthus

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

It's probably a bad idea to plant catharanthus until after all chance of frost has passed because they do not do well in cold weather.

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

The average date of last frost is April 15 in Madison. It might get as low as -10°F during the coldest months of winter.

Keep in mind that USDA zone info for Madison may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Madison there is a last 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 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 Madison

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