When to Plant Pearl onions in Caldwell, ID

Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By referring to the USDA zone info for Caldwell you will be able to determine when to plant pearl onions.


Planting Calendar for Pearl onions

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

Since pearl onions do ok in moderate cold you can plant them just a tiny bit earlier in the year than plants that are more sensitive to the cold.

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

The earliest that you can plant pearl onions in Caldwell 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 pearl onions and expect a good harvest is probably August. Any later than that and your pearl onions may not have a chance to really do well. You can get started a little bit earlier by starting your pearl onions indoors.

Last Frost Date

The average date of last frost is April 15 in Caldwell. You can expect an average low temperature of -5°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Caldwell and it is different every year. Half of the time in Caldwell last frost occurs after April 15 so always be ready to cover your pearl onions if you have a late frost.

USDA Zone Info for Caldwell

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-5°F
Highest Expected Low0°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 0°F.

Plants to Grow in Caldwell

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