Southern California doesn’t have seasons like other parts of the country. Sure, this winter has been particularly wet and there were some blink-and-you’d-miss-them snow flurries in a few pockets around Los Angeles. But when the sun comes out, so do the flip-flops and tank tops. March or May—it doesn’t matter. The way we know spring is on its way is when tickets go on sale for the Pasadena Showcase House for the Arts’ annual fundraiser, the Pasadena Showcase House of Design. It’s the oldest, largest and most successful house and garden tours in the country. Funds raised support a diverse group of recipients from the Los Angeles Opera Company to…