When to Plant Scaevola in Mercer Island, WA

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.

A common way of making a decision about when to plant scaevola is to check out the USDA zone info for Mercer Island.


Planting Calendar for Scaevola

Frost tolerance for scaevola: Not tolerant of frost.
When to plant: After the last frost when the weather gets warmer.

Since scaevola do not do well in cold weather you need to wait until after all chance of frost has passed before you can plant them.

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

The earliest that you can plant scaevola in Mercer Island is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant scaevola and expect a good harvest is probably August. If you wait any later than that and your scaevola may not have a chance to really do well. If you are starting your scaevola indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on March 15 in Mercer Island. It might get as low as 15°F during the coldest months of winter.

Since the USDA zone info for Mercer Island is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Mercer Island you get a frost after March 15 be ready to protect your scaevola if you have a surprise late frost.

USDA Zone Info for Mercer Island

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 Mercer Island

You may be interested in your other planting guides for Mercer Island.