Before planting it is a good idea to find your USDA Zone info to figure out 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.

By checking out the USDA zone info for Humboldt it's a good idea to determine when it's a good idea to plant catharanthus.

Planting Calendar for Catharanthus

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

You can not plant catharanthus until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant catharanthus in Humboldt 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 really do well. Starting your catharanthus indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Humboldt. In the coldest months of winter you can expect an average low temperature of 0°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 Humboldt and it will vary from year to year. Since half of the time in Humboldt last frost occurs after April 15 be ready to protect your catharanthus if you have one of those late frosts.

USDA Zone Info for Humboldt

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Humboldt

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