The best known examples of tubers are potatoes, sweet potatoes, dahlias, begonias, and yams. Each one stores energy underground in a swollen fleshy structure. That stored energy fuels new growth when the right season comes around.
I grow both edible and flower tubers in my garden every year. The two experiences feel quite different from each other. Potatoes are the easiest to start with. You just cut a grocery store potato into pieces with two to three eyes each and plant them in a mound of loose soil. Dahlias need more care since the tuber necks are fragile and snap if you handle them too rough. Begonias fall in between. Their round flat tubers sit on top of moist soil and sprout on their own with almost no fuss at all.
All tubers share the same basic job. They hold water, starches, and nutrients that a plant needs to survive its dormant period and grow again. But tubers are not the same as bulbs or corms. True bulbs like tulips and onions have layered scales wrapped around a center point. Corms like crocus and gladiolus are solid stem bases. Tubers lack any layered structure inside.
The biggest gap between types of tubers shows up in where the growth eyes form. Potato eyes appear all over the tuber body. You can cut one potato into many pieces and each one will grow. Dahlia eyes only form at the crown where the tuber meets the old stem. You must keep that crown intact when dividing or the body alone will never sprout. This one detail makes a huge difference in how you handle each type.
Tuber plants share similar storage needs even though they look quite different. Cool temps between 40°F and 50°F (4°C and 10°C) keep most tubers dormant without drying out. Good air flow stops mold from forming. A dry packing medium like peat moss soaks up extra moisture. These rules work the same for your dahlia clumps, your seed potatoes, and your begonia tubers sitting in the garage over winter.
Once you learn how tubers work you can use that knowledge across every tuber plant you grow. Cut near the eyes when dividing. Cure fresh cuts before you store them. Check stored tubers once a month for rot. These habits keep your tubers healthy season after season no matter which ones you choose to grow in your garden.
Read the full article: Dahlia Tubers: A Complete Growing Guide
