Well it is good that you're giving it a serious thought. That effort is encouraging.
What does he like to drink? Beer? Something else? Maybe you can buy him a nice
six pack of beer then create some kind of simple romantic dinner with candle lights around Valentine's night. If you're sneaky enough, have this personal shindig on the night before Valentine's so it will catch him off guard.
You could give him some homemade coupons for say future shoulder massages. It might be appreciated if he has a stressful job and/or week.