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.

You can estimate when it's a good idea to plant platycodon in Northfield by using 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 do ok in some cold which tells us that you can plant them slightly earlier in the year than more sensitive plants.

The earliest that you can plant platycodon in Northfield is April. However, you really should wait until May 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. If you wait any later than that and your platycodon may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your platycodon indoors.

Last Frost Date

On average the last frost is on May 15 in Northfield. It might get as low as -25°F during the coldest months of winter.

Remember that USDA zone info for Northfield may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in Northfield last frost occurs after May 15 be ready to cover your platycodon in the event of one of those late frosts.

USDA Zone Info for Northfield

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Northfield

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