When to Plant Diascia in Seattle, WA

One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can estimate when you can plant diascia in Seattle by checking out the USDA zone info.


Planting Calendar for Diascia

Frost tolerance for diascia: Tolerant of some frost.
When to plant: Up to 5 weeks before last frost.

Diascia do ok in mild cold which means that you can plant them a little bit earlier in the year than more sensitive plants.

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

The earliest that you can plant diascia in Seattle is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant diascia and expect a good harvest is probably September. Any later than that and your diascia may not have a chance to really do well. If you are starting your diascia indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Seattle. You should expect an average low temperature of 15°F in the coldest months of winter.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Seattle and it can change quite a bit from year to year. Half of the time in Seattle there is a last frost after March 15 so make sure that you are ready to cover your diascia in the event of a late frost.

USDA Zone Info for Seattle

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 Seattle

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