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

The USDA zone info for Snohomish should be read to figure out when to plant alternanthera.

Planting Calendar for Alternanthera

Frost tolerance for alternanthera:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since alternanthera do not do well in cold weather it's important to wait until after the last frost before you can plant them.

The earliest that you can plant alternanthera in Snohomish is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant alternanthera and expect a good harvest is probably August. If you wait any later than that and your alternanthera may not have a chance to grow to maturity. Starting your alternanthera indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on March 15 in Snohomish. It might get as low as 15°F during the coldest months of winter.

It's important to remember that USDA zone info for Snohomish is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Snohomish it frosts late in the year after March 15 be ready to protect your alternanthera in the event of one of those late frosts.

USDA Zone Info for Snohomish

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Snohomish

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