The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of determining when it's the best time to plant scallions is to consult the USDA zone info for Umatilla.

Planting Calendar for Scallions

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

Scallions tend to make it in a tiny bit of cold which tells us that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant scallions in Umatilla 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 scallions and expect a good harvest is probably August. You probably don't want to wait any later than that or else your scallions may not have a chance to grow to maturity. Starting your scallions indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Umatilla the average date of last frost happens on April 15. It might get as low as 5°F during the coldest months of winter.

Since the USDA zone info for Umatilla is an average the actual date of last frost changes from year to year. Since half of the time in Umatilla you get surprised by a frost after April 15 be ready to protect your scallions if you have a late frost.

USDA Zone Info for Umatilla

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Umatilla

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