Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant platycodon in New Castle should be estimated by referring to the USDA zone info.

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 can survive in some cold which means that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant platycodon in New Castle 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 grow to maturity. 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

In New Castle the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Always keep in mind that USDA zone info for New Castle may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in New Castle it frosts late in the year after April 15 so just be sure to be ready to protect your platycodon if you have a surprise late frost.

USDA Zone Info for New Castle

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°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 -10°F.

Plants to Grow in New Castle

You may be interested in your other planting guides for New Castle.