The USDA Zone info is a great tool for gardeners to help us figure out 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.

In Johnston you can determine when it's possible to plant redvein dock by looking at the USDA zone info.

Planting Calendar for Redvein Dock

Frost tolerance for redvein dock:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant redvein dock a bit earlier in the year because they are barely cold tolerant.

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

The last month that you can plant redvein dock and expect a good harvest is probably August. If you wait any later than that and your redvein dock may not have a chance to fully mature. If you are starting your redvein dock indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Johnston the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Johnston is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Johnston last frost occurs after April 15 be ready to protect your redvein dock if you have a surprise 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.