When to Plant Pearl onions in Maple Valley, WA

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.

By using the USDA zone info for Maple Valley it's possible to figure out when it's possible 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.

You can plant pearl onions just a tiny bit earlier in the year because they do ok in moderate 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 Maple Valley 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. If you wait any later than that and your pearl onions may not have a chance to grow to maturity. If you are starting your pearl onions indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Maple Valley the average date of last frost happens on March 15. You can expect an average low temperature of 15°F in the coldest months of winter.

Since the USDA zone info for Maple Valley is just an average the actual date of last frost changes from year to year. Since half of the time in Maple Valley you get surprised by a frost after March 15 be ready to protect your pearl onions in the event of a surprise late frost.

USDA Zone Info for Maple Valley

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 Low15°F
Highest Expected Low20°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 Maple Valley

You may be interested in your other planting guides for Maple Valley.