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.

One way of determining when it's a good idea to plant alstromeria is to check out the USDA zone info for Caribou.

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 bit 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 Caribou 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. You probably don't want to wait any later than that or else 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

On average all chance of frost has passed is on May 15 in Caribou. It might get as low as -30°F during the coldest months of winter.

Since the USDA zone info for Caribou is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Caribou last frost occurs after May 15 be ready to cover your alstromeria in the event of one of those late frosts.

USDA Zone Info for Caribou

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 Caribou

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