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.

The USDA zone info for Johnston can be read to determine when you can plant balloon flower.

Planting Calendar for Balloon Flower

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

Balloon Flower can survive in mild cold which tells us that you can plant them slightly earlier in the year than more sensitive plants.

The earliest that you can plant balloon flower 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 balloon flower and expect a good harvest is probably August. If you wait any later than that and your balloon flower may not have a chance to really do well. Starting your balloon flower indoors is a great way to get them started a little bit 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.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Johnston and it is different every year. Since half of the time in Johnston last frost occurs after April 15 be ready to protect your balloon flower 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.