If you want your springtime blooms with an iconic view, the Grinpa Heavenly Tulip Festival is one to pencil in on your calendar. 130,000 tulips in 18 varieties are set against the backdrop of Mount Fuji (on clear days!), creating a breathtaking scene.
There are also a host of fun photo spots set up over the amusement park grounds, and soft serve ice creams flavored with tulip extract available to buy.
Do note that like any flower festival, the dates can be subject to change depending on blooming conditions. It's advisable to check the official website before you plan on attending, but a rough estimate is from mid-April through to mid/late May.
I'm eyeing some started tulips at my local home center. They're already available in the Tokyo area.