When to Plant Cosmos in Newton, MA

One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The best time to plant cosmos in Newton should be figured out by reviewing the USDA zone info.


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.

You can plant cosmos slightly earlier in the year because they do ok in moderate cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant cosmos
Possibly ok, but a risky time to plant cosmos
Probably not a good time to plant cosmos

The earliest that you can plant cosmos in Newton 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. Any later than that and your cosmos may not have a chance to really do well. You can get started a little bit earlier by starting your cosmos indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Newton. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for Newton is an average the actual date of last frost changes from year to year. Half of the time in Newton you get surprised by a frost after April 15 so make sure that you are prepared to protect your cosmos in the event of one of those late frosts.

USDA Zone Info for Newton

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 Low0°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 Newton

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