One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Watertown you can estimate when it's possible to plant asters by using the USDA zone info.

Planting Calendar for Asters

Frost tolerance for asters:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Asters tend to make it in mild cold which tells us that you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant asters in Watertown is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant asters and expect a good harvest is probably September. Any later than that and your asters may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your asters indoors.

Last Frost Date

The average date of last frost is April 15 in Watertown. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for Watertown is an average the actual date of last frost will vary from year to year. Since half of the time in Watertown you get a frost after April 15 be ready to protect your asters in the event of a late frost.

USDA Zone Info for Watertown

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 Watertown

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