One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to figure out when it's the best time to plant tree onions by looking at the USDA zone info for Pasco.

Planting Calendar for Tree onions

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

Tree onions do ok in some cold which tells us that you can plant them just a tiny bit earlier in the year than more sensitive plants.

The earliest that you can plant tree onions in Pasco 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 tree onions and expect a good harvest is probably August. Any later than that and your tree onions may not have a chance to fully mature. If you are starting your tree onions indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Pasco. You can expect an average low temperature of 0°F in the coldest months of winter.

It's important to remember that USDA zone info for Pasco is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Pasco you get a frost after April 15 so make sure that you are prepared to protect your tree onions in the event of one of those late frosts.

USDA Zone Info for Pasco

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Pasco

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