PLAYTHINGS

Johnny Carson is not the only nocturnal monarch in retirement: The California king-size mattress is about to join him.

In the 1940s, when only twin- and full-sized beds existed, a Wilshire Boulevard shopkeeper began offering a luxurious 6-by-7-foot version, says Don Simon, chairman of the International Sleep Products Assn. As demand for bigger beds spread East, some manufacturers changed the dimensions to make them cheaper to produce. Californians, however, continued to doze away on the original.

Four inches narrower and four inches longer than the Eastern king, the California king and its linen have befuddled sheet-shopping L.A. transplants for years. California king owners are no better off. “We get calls from people who’ve moved East for Cal king-size sheets,” says Allen Josephson, vice president of merchandising for Strouds.

But that’s about to change. Last spring, the trade group dropped the California king from its specifications guidelines to make life easier for people moving to or from California. Although some retailers are a bit miffed, industry leaders insist that consumers will find the transition, which will occur between now and the year 2000, as gentle as a lullabye. But local stores are taking precautions. “We’re planning on hoarding the sheets,” says Mark Grand, vice president of store operations with Strouds. “Customers who already own California king beds are going to need bed linens.”