Are you starting all your seeds indoors? You must have a lot of seed-starting space for that many varieties.
I realized that part of my garage clutter problem is actually all the supplies on hand for undone projects. So, my garage item today was to finally replace the ratty liners for the hanging fern baskets and replant the ferns with nice fresh soil. Also, I replaced the old potting soil in a few of the pots I brought in. Finishing up that bag of soil means another couple feet of available floor space, and the pots are ready for new plants in the Spring. The best part was that playing in the dirt was such a nice distraction from winter.
Bummer on the bird seed mess. Whatever you do, don't open the door or you'll have a garage full of birds!