Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. 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 alstromeria in Watertown should be estimated by looking at the USDA zone info.

Planting Calendar for Alstromeria

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

Alstromeria do ok in mild cold which means that you can plant them just a bit earlier in the year than more sensitive plants.

The earliest that you can plant alstromeria in Watertown 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 alstromeria and expect a good harvest is probably August. If you wait any later than that and your alstromeria may not have a chance to grow to maturity. Starting your alstromeria indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Watertown. You should expect an average low temperature of -30°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Watertown is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Watertown there is a last frost after May 15 be ready to protect your alstromeria in the event of one of those late frosts.

USDA Zone Info for Watertown

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Watertown

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