Whether begonias come back yearly depends on your climate and the type you grow. In frost-free areas they return on their own, but in cold regions most die at the first hard freeze. So the honest answer is it depends, and the rest of this answer shows you why and what to do about it.
"Those begonias will never make it through winter," my neighbor said, leaning over the fence one October. The wax begonia in my damp, partly shaded border did die back and never returned. But the tuberous ones I dug up and stored in pots on my back porch pushed out new shoots the next summer.
So are begonias perennials or annuals? They are perennials by nature. Almost all of them are tender perennials, which means a hard frost kills the plant outright. In warm zones the roots and tubers live through winter and grow again. In cold zones that same frost ends them, so gardeners treat them as one-season annuals.
Your climate draws the line. Begonias come back on their own outdoors in USDA Zones 8b to 11, where winters stay mild and the ground rarely freezes. North of that the cold reaches the roots and your plant cannot recover. This is why a begonia sold as a perennial in Florida acts like a throwaway annual in Ohio.
Your begonia type matters as much as your zone. Tuberous types grow from a fat underground tuber that can survive winter if you keep it from freezing. Wax begonias, the small bedding kind, have fine roots that frost wipes out. Cane and Rex types live as houseplants but will not last a cold winter outside in the ground.
One type breaks the rule. The hardy begonia, Begonia grandis, returns from its roots down to Zone 7. It dies back to the ground each fall and pushes up fresh growth in late spring, much like a hosta. If you garden in a colder spot and want a begonia that comes back without any fuss, this is the one to plant.
There is one more quirk worth knowing. Tuberous begonias go dormant every year no matter how you grow them, even in a warm greenhouse. So they are not true year-round houseplants. The plant naturally rests for a stretch, then wakes and grows again. Plan for that pause and you will not think you have lost a plant when it simply takes its winter nap.
In a cold climate you still get them back, but you have to step in. Dig up your tuberous begonias after the first light frost browns the leaves. Brush off the soil and let the tubers dry for a few days. Then store them in peat or vermiculite at 40 to 55°F (4 to 13°C). Replant them in spring and they grow again, year after year.
Keep a few things in mind while your tubers rest through winter. Check them once a month and toss any that feel soft or look moldy. A cool basement or a garage that never freezes works well for storage. Keep them dark and dry, and do not let them sit near a heat vent that would dry them out or wake them up too soon.
Bring your cane and Rex begonias indoors before the cold hits. They make fine houseplants on a bright windowsill. These living plants carry over far better than bedding wax types. So save your tubers and move the leafy ones inside. Tender perennial begonias reward a little fall effort, and you skip the cost of buying new plants every spring.
Read the full article: Begonias Plants: Full Care Guide
