When to Plant Lobelia in Issaquah, WA

The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant lobelia in Issaquah should be estimated by using the USDA zone info.


Planting Calendar for Lobelia

Frost tolerance for lobelia: Very tolerant of frost.
When to plant: Up to 7 weeks before last frost.

You can plant lobelia a lot earlier in the year because they do well in cold.

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

The earliest that you can plant lobelia in Issaquah 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 lobelia and expect a good harvest is probably September. If you wait any later than that and your lobelia may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your lobelia indoors.

Last Frost Date

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

Since the USDA zone info for Issaquah is not always accurate the actual date of last frost is different every year. Half of the time in Issaquah last frost occurs after March 15 so make sure that you are prepared to cover your lobelia if you have a surprise 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.