One of the best tools that you have as gardeners to help us estimate 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.

A way of figuring out when it's the best time to plant spinach is to look at the USDA zone info for Watertown.

Planting Calendar for Spinach

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

Since spinach are moderately cold tolerant you can plant them a little bit earlier in the year than other plants that might not handle the cold.

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

Last Frost Date

In Watertown the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Watertown and it can change quite a bit from year to year. Half of the time in Watertown it frosts late in the year after April 15 so be sure to be ready to cover your spinach in the event of a late frost.

USDA Zone Info for Watertown

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Watertown

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