When to Plant Alyssum in Washington, IL

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.

You can estimate when to plant alyssum in Washington by referring to the USDA zone info.


Planting Calendar for Alyssum

Frost tolerance for alyssum: Very tolerant of frost.
When to plant: Up to 7 weeks before last frost.

Alyssum do ok in pretty solid cold which means that you can plant them quite a bit earlier in the year than other frost tender plants.

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

The earliest that you can plant alyssum 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 alyssum and expect a good harvest is probably September. You probably don't want to wait any later than that or else your alyssum may not have a chance to fully mature. You can get started a little bit earlier by starting your alyssum indoors.

Last Frost Date

On average the last frost is on April 15 in Washington. You can expect an average low temperature of -15°F in the coldest months of winter.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Washington and it can change quite a bit from year to year. Half of the time in Washington it frosts late in the year after April 15 so just be sure to be ready to protect your alyssum 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.