When my dear aunt was 100, I did a “100 bulbs for 100 years” present. I got nice large glazed pots and layered all the bulbs, layer of compost first, largest bulbs at the bottom, another layer of compost, right up to tiny bulbs at the top, finishing with a layer of little pebbles/grit. The biggest ones grow through and there is a succession of flowers. I needed 2 large pots as there were so many bulbs. There are lots of nice bulbs available in late August and September, and a nursery could advise you which would work best. I think I used tulips, daffs, grape hyacinths and Scilla in colours which went well together. And dressed the pots up with big bows. She was delighted, and rang me several times with updates of what had come up. They also reappeared the following year. Can prove expensive though, depending on which pots and bulbs you choose. Wasn’t an issue with my aunt, but you may not want to spend so much on a neighbour