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.

By referring to the USDA zone info for Douglas you should be able to figure out when you can plant platycodon.

Planting Calendar for Platycodon

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

Since platycodon are barely cold tolerant you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant platycodon in Douglas 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 platycodon and expect a good harvest is probably August. Any later than that and your platycodon may not have a chance to really do well. If you are starting your platycodon 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 March 15 in Douglas. It might get as low as 15°F during the coldest months of winter.

Since the USDA zone info for Douglas is just an average the actual date of last frost will vary from year to year. Half of the time in Douglas it frosts late in the year after March 15 so always be ready to cover your platycodon in the event of a late frost.

USDA Zone Info for Douglas

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Douglas

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