One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Johnston you will be able to figure out when it's possible to plant missouri primrose.

Planting Calendar for Missouri Primrose

Frost tolerance for missouri primrose:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Missouri Primrose do well in mild cold which means that you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant missouri primrose 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 missouri primrose and expect a good harvest is probably September. You probably don't want to wait any later than that or else your missouri primrose may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your missouri primrose indoors.

Last Frost Date

The average date of last frost is April 15 in Johnston. In the coldest months of winter you should expect an average low temperature of -20°F.

Remember that USDA zone info for Johnston is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Johnston there is a last frost after April 15 so always be ready to protect your missouri primrose if you have 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.