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

It's possible to determine when it's the best time to plant larkspur by referring to the USDA zone info for Watertown.

Planting Calendar for Larkspur

Frost tolerance for larkspur:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Larkspur tend to make it in a bit of cold which means that you can plant them earlier in the year than other frost tender plants.

The earliest that you can plant larkspur 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 larkspur and expect a good harvest is probably September. Any later than that and your larkspur may not have a chance to fully mature. You can get started a few weeks earlier by starting your larkspur 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.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Watertown and it can change quite a bit from year to year. Since half of the time in Watertown there is a last frost after April 15 be ready to protect your larkspur if you have one of those late frosts.

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.