Bulbs, rhizomes and tubers
The main difference between bulbs and the other three is bulbs grow scales, layers, around a core, whereas corms, rhizomes and tubers are solid all the way through, but all of them serve the same function: they store starch so the plants can use it for energy.
Bulbs, corms, rhizomes and tubers are the easiest and fastest way to populate a border. Just dig a hole, add a good handful of bone meal, layer the bulbs according to their recommended planting depth and, come spring, you’ll have a flower garden.
Just a few things about planting bulbs.
Respect the recommended planting depth, or the plants will sprout too early or too late.
Place the corms up side up. They look like little pebbles, so it’s kind of hard to tell.
Rhizomes and tubers grow horizontally and spread that way, so you can cut them into pieces to multiply your stock. Every piece should have at least two or three eyes (growth buds), and a healthy root system. Plant them right under the soil’s surface.
Bulbs and corms are usually started in the fall, even for summer perennials; you can plant rhizomes and tubers any time during their growing season.