California is toward the end of its Native Plant Week, April 15-23, with many events organized through the California Native Plant Society.
For more information on events in California see the California Native Plant Week events page.
Oregon’s Native Plant Appreciation Week starts this Sunday, April 23rd, running through April 29th. The Native Plant Society of Oregon (NPSO) also has many events planned for the week. NPSO Facebook page
For Siskiyou Chapter Native Plant Society of Oregon Native Plant Appreciation Week events see their Facebook page.