One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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 Green River it's a good idea to determine when it's a good idea to plant alstromeria.

Planting Calendar for Alstromeria

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

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

The earliest that you can plant alstromeria in Green River 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 fully mature. If you are starting your alstromeria indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Green River the average date of last frost happens on May 15. You should expect an average low temperature of -25°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Green River and it changes from year to year. Since half of the time in Green River it frosts late in the year after May 15 be ready to protect your alstromeria if you have a late frost.

USDA Zone Info for Green River

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Green River

You may be interested in your other planting guides for Green River.