One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Walla Walla can be looked at 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.

Platycodon do ok in a tiny bit of 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 platycodon in Walla Walla 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. You probably don't want to wait any later than that or else your platycodon may not have a chance to fully mature. If you are starting your platycodon indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Walla Walla. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Walla Walla is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Walla Walla it frosts late in the year after April 15 so make sure that you are ready to protect your platycodon in the event of a surprise late frost.

USDA Zone Info for Walla Walla

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 Walla Walla

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