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.

The best time to plant catharanthus in Oshkosh should be figured out 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 when the weather gets warmer.

Catharanthus do not do well in cold weather which means that you need to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant catharanthus in Oshkosh 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. If you wait 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

In Oshkosh the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -20°F.

Since the USDA zone info for Oshkosh is not always accurate the actual date of last frost changes from year to year. Since half of the time in Oshkosh it frosts late in the year after April 15 be ready to protect your catharanthus in the event of one of those late frosts.

USDA Zone Info for Oshkosh

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Oshkosh

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