One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Johnston you can estimate when it's possible to plant lemon grass by using the USDA zone info.

Planting Calendar for Lemon grass

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

Lemon grass can survive in mild cold which tells us that you can plant them slightly earlier in the year than other plants that might not handle the cold.

The earliest that you can plant lemon grass 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 lemon grass and expect a good harvest is probably August. If you wait any later than that and your lemon grass may not have a chance to fully mature. If you are starting your lemon grass 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 when the weather gets warmer is on April 15 in Johnston. In the coldest months of winter you should expect an average low temperature of -20°F.

Since the USDA zone info for Johnston is not always accurate the actual date of last frost is different every year. Half of the time in Johnston it frosts late in the year after April 15 so just be sure to be ready to protect your lemon grass in the event of 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.