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

You will be able to determine when it's possible to plant hamburg root parsley by referring to the USDA zone info for Johnston.

Planting Calendar for Hamburg root parsley

Frost tolerance for hamburg root parsley:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Hamburg root parsley do well in moderate cold which means that you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant hamburg root parsley 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 hamburg root parsley and expect a good harvest is probably September. If you wait any later than that and your hamburg root parsley may not have a chance to grow to maturity. If you are starting your hamburg root parsley indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Johnston is just an average the actual date of last frost is different every year. Half of the time in Johnston there is a last frost after April 15 so just be sure to be ready to protect your hamburg root parsley 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.