The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By checking out the USDA zone info for Somerville you should be able to estimate when it's the best time to 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 well 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 Somerville 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 grow to maturity. You can get started a couple of weeks earlier by starting your platycodon indoors.

Last Frost Date

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

Since the USDA zone info for Somerville may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Somerville you get surprised by a frost after April 15 be ready to cover your platycodon in the event of a late frost.

USDA Zone Info for Somerville

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 Somerville

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