The USDA Zone info is a great tool for gardeners to help us estimate your gardening 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 Johnston it's a good idea to determine when it's possible to plant carnation.

Planting Calendar for Carnation

Frost tolerance for carnation:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Carnation tend to make it in a bit of cold which means that you can plant them a lot earlier in the year than other plants that might not handle the cold.

The earliest that you can plant carnation in Johnston is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant carnation and expect a good harvest is probably September. You probably don't want to wait any later than that or else your carnation may not have a chance to really do well. If you are starting your carnation indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Johnston. It might get as low as -20°F during the coldest months of winter.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Johnston and it can change quite a bit from year to year. Half of the time in Johnston you get surprised by a frost after April 15 so just be sure to be ready to cover your carnation if you have a late frost.

USDA Zone Info for Johnston

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 Johnston

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