When to Plant Schizanthus in Mercer Island, WA

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.

You can figure out when it's the best time to plant schizanthus in Mercer Island by referring to the USDA zone info.


Planting Calendar for Schizanthus

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

Schizanthus require warm weather which tells us that you really should wait until it warms up after the last frost has passed before you can plant them.

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

The earliest that you can plant schizanthus 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 schizanthus and expect a good harvest is probably August. If you wait any later than that and your schizanthus may not have a chance to really do well. You can get started a little bit earlier by starting your schizanthus indoors.

Last Frost Date

On average the last frost has passed is on March 15 in Mercer Island. You can expect an average low temperature of 15°F in the coldest months of winter.

Remember that USDA zone info for Mercer Island is just an average and the actual date of last frost changes from year to year. Half of the time in Mercer Island it frosts late in the year after March 15 so always be ready to cover your schizanthus if you have one of those late frosts.

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.