One of the first steps you take when you are figuring out 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.

By referring to the USDA zone info for Watertown you will be able to estimate when you can plant alstromeria.

Planting Calendar for Alstromeria

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

You can plant alstromeria a little earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant alstromeria 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 alstromeria and expect a good harvest is probably September. Any later than that and your alstromeria may not have a chance to really do well. If you are starting your alstromeria indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Watertown. In the coldest months of winter you should expect an average low temperature of -5°F.

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 changes from year to year. Half of the time in Watertown there is a last frost after April 15 so always be ready to protect your alstromeria in the event of a surprise 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.