I have become an expert on hanging baskets through a very practical process. I just no longer try to grow things that I habitually kill. So the few things I do grow do well.
Hanging off the rail of the deck is a line of several fire engine red dipladenias, or as I have always called them, mandevillas. Taxonomists are having their usual spat about that. Long a plant only for the deep south, the last couple of years they have been showing up by the truckload in big box stores, handsome plants at a handsome price.
You may wonder how someone who hates to pull more than one bill at a time from his wallet got a whole row of these. As it turns out, some growers actually put three or four separate cuttings in each pot. You need to burrow down through the leaves and flowers and see how many stems come out of the soil. You can separate them, so instead of having one $20 pot you can have four $5 pots. That I can live with.
Given its druthers, mandevilla is a trailing or climbing plant, but the ones you buy are shrubby. They have been drugged. The big wholesale greenhouses spray them with a growth retardant, which does two things. It keeps them compact and shrubby and it makes them bloom earlier so that you buy them. But it doesn't last forever, and by late summer they will start to reach out into long vines, either climbing or trailing depending on where you have them.
Mandevillas can be overwintered in a sunny spot indoors, but there is a drawback. The growth retardant will have long since worn off, so they will start the next season growing long vines. That can be a good thing if that is what you wanted in the first place. But they won't start blooming well until later in the summer. If you want to overwinter it, cut it way back before you bring it inside. Or you can just buy new ones. Or both.
Mandevillas need lots and lots of sun. Hanging them in baskets from lower tree branches is not a good option. But that is the perfect spot for tuberous begonias. The best situation for them is where they get some sunlight peeking in in the morning and/or late afternoon with maybe some filtered sun through the branches during the day.
For decades I have grown the large flowered hybrids, the brown lumps in plastic bags in the stores in spring, usually from Belgium, sometimes if I am lucky and flush from California. They put the lie to the idea that shade plants are dull.
Lately though a new kind of tuberous begonia has been showing up, not with a few huge blooms but scores of smaller flowers. They are very graceful in a hanging basket, and hummingbirds love them.
I first got begonia Skaugum about four years ago, a great basket plant. Then I ran across Bonfire from Tesselaar, a cousin rather than a sibling, and that was even better. This spring I found a Chocolate Bonfire, and wow! I'm always a sucker for bright flowers against dusky foliage.
These begonias are usually grown from cuttings, not tubers, with the hope that you will throw them out in fall and buy new ones next spring. But they do form tubers, some very big tubers, if you keep them growing well into fall. They can be stored and started just like any tuberous begonia.
All of these plants have one thing in common: They have lived in spite of my care. Unlike many plants common to baskets, these will not die with the haphazard watering they are apt to get here.
Duane Campbell is a nationally known agricultural expert. He can be reached at R6, Box 6029, Towanda, PA, 18848 or e-mail at email@example.com