Somebody sent Kevin Kline the petals from two dozen roses while he was staying at the Jefferson Hotel here recently. What does this mean?

The Harlequin Dinner Theatre (currently offering "The Pirates of Penzance") reports a 60 percent increase in subscription tickets this season over last. The demand was so great, according to the public relations office, that the subscription drive was closed four months ahead of schedule . . . The New Playwrights' theater raised more than $27,000 from its recent VIP benefit. Since New Playwrights' expected $20,000, officials are quite pleased . . . And Living Stage raised enough at its benefit last week, plus some other funds, to pay for another month of performances at schools and other institutions: $10,700.

The Folger Theatre reports that initial efforts to start a conservatory have been successful. More than 70 students are enrolled in the second 10-week session. The D.C. Council on the Arts supplied a grant of $2,000 for scholarships, which were given in full to five students and in part to eight others. The most popular courses are those in acting Shakespeare, which require an audition. But . . . there is still room in two courses: Audition Technique, taught by artistic director John Neville-Andrews, and Movement for the Professional Actor, taught by Claudia Neely. Call 547-5666 . . .

Speaking of courses, playwright Ernie Joselovitz is heading a professional workshop for playwrights. It includes a director and actors to read scenes. Participants need not have been produced, although some have, but they must have a written script read before being admitted to the couple. Call 232-4527.