One of the best tools that you have as gardeners to help us figure out 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.

A common way of determining when it's possible to plant gomphrena is to use the USDA zone info for Snohomish.

Planting Calendar for Gomphrena

Frost tolerance for gomphrena:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Gomphrena do ok in moderate cold which tells us that you can plant them slightly earlier than other plants that might not handle the cold.

The earliest that you can plant gomphrena in Snohomish 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 gomphrena and expect a good harvest is probably August. If you wait any later than that and your gomphrena may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your gomphrena indoors.

Last Frost Date

The average date of last frost is March 15 in Snohomish. In the coldest months of winter you should expect an average low temperature of 15°F.

It's important to remember that USDA zone info for Snohomish may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in Snohomish last frost occurs after March 15 be ready to protect your gomphrena if you have a surprise late frost.

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.