When to Plant Alstromeria in Washington, IL

Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant alstromeria in Washington can 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.

Since alstromeria do well in moderate cold you can plant them just a bit earlier in the year than more sensitive plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant alstromeria
Possibly ok, but a risky time to plant alstromeria
Probably not a good time to plant alstromeria

The earliest that you can plant alstromeria in Washington 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. You probably don't want to wait any later than that or else your alstromeria may not have a chance to fully mature. Starting your alstromeria indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Washington. In the coldest months of winter you can expect an average low temperature of -15°F.

It's important to remember that USDA zone info for Washington is just an average and the actual date of last frost changes from year to year. Since half of the time in Washington you get surprised by a frost after April 15 be ready to cover your alstromeria in the event of a late frost.

USDA Zone Info for Washington

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-15°F
Highest Expected Low-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Washington

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