One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to estimate when it's the best time to plant salpiglossis by looking at the USDA zone info for Issaquah.

Planting Calendar for Salpiglossis

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

You really shouldn't plant salpiglossis until after the last frost has passed because they do not do well in cold weather.

The earliest that you can plant salpiglossis 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 salpiglossis and expect a good harvest is probably August. Any later than that and your salpiglossis may not have a chance to grow to maturity. Starting your salpiglossis indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Issaquah the average date of last frost happens on March 15. In the coldest months of winter you can expect an average low temperature of 15°F.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Issaquah and it will vary from year to year. Since half of the time in Issaquah there is a last frost after March 15 be ready to protect your salpiglossis 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 Low	15°F
Highest Expected Low	20°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.