Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for New Boston should be reviewed to estimate when to plant cosmos.

Planting Calendar for Cosmos

Frost tolerance for cosmos:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since cosmos are barely cold tolerant you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant cosmos in New Boston 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 cosmos and expect a good harvest is probably August. You probably don't want to wait any later than that or else your cosmos may not have a chance to grow to maturity. If you are starting your cosmos indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In New Boston the average date of last frost happens on March 15. In the coldest months of winter you should expect an average low temperature of 10°F.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for New Boston and it is different every year. Half of the time in New Boston you get a frost after March 15 so always be ready to cover your cosmos if you have one of those late frosts.

USDA Zone Info for New Boston

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in New Boston

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