When to Plant Calliopsis in Issaquah, 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.

The earliest that you can plant calliopsis in Issaquah should be estimated by reviewing the USDA zone info.


Planting Calendar for Calliopsis

Frost tolerance for calliopsis: Not tolerant of frost.
When to plant: After the last frost has passed.

Calliopsis do not do well in cold weather which tells us that it is necessary to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

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

The earliest that you can plant calliopsis in Issaquah 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 calliopsis and expect a good harvest is probably August. Any later than that and your calliopsis may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your calliopsis indoors.

Last Frost Date

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

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Issaquah and it can change quite a bit from year to year. Half of the time in Issaquah you get a frost after March 15 so make sure that you are ready to protect your calliopsis if you have a late frost.

USDA Zone Info for Issaquah

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 Issaquah

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