One of the first steps you take when you are getting a good idea 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.

You should be able to determine when to plant platycodon by using the USDA zone info for Caldwell.

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 just a tiny bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant platycodon in Caldwell 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. You can get started a little bit earlier by starting your platycodon indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Caldwell. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for Caldwell is just an average the actual date of last frost is different every year. Half of the time in Caldwell it frosts late in the year after April 15 so make sure that you are ready to cover your platycodon if you have a surprise late frost.

USDA Zone Info for Caldwell

Here is the info for USDA Zone 6b.

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

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

Plants to Grow in Caldwell

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