Need to Google under the botanical name

Try:

www.ussl.ars.usda.gov/pls/caliche/BOROT46

Applying the stuff can be very touchy. Just a little bit can be too much.

Do gardeners around Puget Sound need boron?

Perhaps you should call your county's Extension Service office -- they would have the info you need.

Are your plants symptomatic? You can get into a can of worms when dealing with micronutrient supplementation. I remember sitting in a lecture concerning boron/molybdenum balance in poinsettia production. If I remember correctly, too much of one will suppress absorption of the other. It's a fine line.

If you talk to growers of specialty crops like fig and citrus, and find they routinely use micronutrient supplements, don't automatically assume it's associated with growing that fruit and you'll always need it. Some localities where these crops are typically grown may just have soils or water deficient in those minerals.

My suggestion is to contact your county extention agent and he/she can connect you with an appropriate resource to answer specific cultural questions.