When to Plant Catharanthus in Zone 1a

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.

By using the USDA zone info for Zone 1a it's a good idea to figure out when to plant catharanthus.


Planting Calendar for Catharanthus

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

Since catharanthus do not do well in cold weather you need to wait until after the last frost when the weather gets warmer before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant catharanthus
Possibly ok, but a risky time to plant catharanthus
Probably not a good time to plant catharanthus

The earliest that you can plant catharanthus in Zone 1a is June. However, you really should wait until July if you don't want to take any chances.

The last month that you can plant catharanthus and expect a good harvest is probably July. If you wait any later than that and your catharanthus may not have a chance to grow to maturity. Starting your catharanthus indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on June 15 in Zone 1a. You can expect an average low temperature of -60°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Zone 1a and it changes from year to year. Since half of the time in Zone 1a it frosts late in the year after June 15 be ready to protect your catharanthus if you have one of those late frosts.

USDA Zone Info for Zone 1a

Here is the info for USDA Zone 1a.

Average Date of Last Frost (spring)June 15
Average Date of First Frost (fall)July 15
Lowest Expected Low-60°F
Highest Expected Low-55°F

This means that on a really cold year, the coldest it will get is -60°F. On most years you should be prepared to experience lows near -55°F.

Plants to Grow in Zone 1a

You may be interested in your other planting guides for Zone 1a.