The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By checking out the USDA zone info for Johnston you will be able to determine when it's the best time to plant iresene.

Planting Calendar for Iresene

Frost tolerance for iresene:	Not tolerant of frost.
When to plant:	After the last frost has passed.

You really shouldn't plant iresene until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant iresene in Johnston 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 iresene and expect a good harvest is probably August. Any later than that and your iresene may not have a chance to really do well. Starting your iresene indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Johnston and it will vary from year to year. Half of the time in Johnston you get surprised by a frost after April 15 so be sure to be ready to protect your iresene in the event of one of those late frosts.

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.