One of the best tools that you have as gardeners to help us determine 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.

The first chance to plant balloon flower in Portland can be estimated by looking at the USDA zone info.

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.

You can plant balloon flower just a tiny bit earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant balloon flower in Portland 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. Any later than that and your balloon flower may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your balloon flower indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Portland. You can expect an average low temperature of 0°F in the coldest months of winter.

Always keep in mind 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 Portland and it changes from year to year. Half of the time in Portland last frost occurs after April 15 so make sure that you are prepared to protect your balloon flower in the event of a surprise late frost.

USDA Zone Info for Portland

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Portland

You may be interested in your other planting guides for Portland.