The long-range weather forecast looks promising, with even night-time temperatures above freezing for the next two weeks. Although the ground is still too cold to dig for general planting, we can certainly get started with tender summer bulbs.
Dahlias, cannas and tuberous begonias are showy perennial flowers that are not hardy enough to winter outdoors in our climate. They bloom all summer, so are well worth enjoying as one-season annuals and discarding in fall — but their roots form plump rhizomes or tubers that store well indoors through winter, so are well-adapted to carrying over for many seasons.
Give these heat-loving plants a head-start by planting them in pots now. This will provide you with a more robust, bud-and-bloom plant to transplant into the garden, and you won’t have to remember where you buried the roots as you tend and plant the rest of the garden.
Retrieve any stored bulbs, remove packing material and check them over to make sure they are still firm. Do the same with any newly purchased bulbs. There is still plenty of stock available at the garden centers and ample time to order plants from your favorite catalog or website.
For tubers destined to plant in the garden, I reuse old plastic pots saved from past plant purchases. I select a pot an inch or two wider than the roots. Those planned for decorative planters are planted directly into those containers. Use fresh professional potting mix like Miracle-Gro or Baccto. Once potted, place on a garden cart to sit outdoors in a sunny spot on warm days, and if freezing weather threatens again, wheel into a sheltered spot until things improve.
Dahlias come in just about every color in the rainbow, an amazing array of flower shapes, from rounded little buttons, full pompons, shaggy cactus to simple daisies, and sizes from a petite two-inches to dinner-plate-sized showpieces. I am particularly fond of the modern smaller-flowered types, which hold blooms up and outward-facing for the best show, and new flowers grow above and hide the fading ones.
I don’t often buy begonia bulbs, but I really like the newer boliviensis types. These are fantastic in hanging baskets and other containers, with a pendulous growth habit and smaller, but very prolific flowers that hang like bells. Blooms are mostly white, yellow and shades of red. I like to buy blooming plants in spring, and winter the tubers in their pots for following seasons. It’s easy, saves money, and spares me the challenge of figuring out which is the top of the bulb.
Last year I had decided to replace most of my canna roots and start fresh. Many of my old stock were showing sights of a virus that causes distorted leaves and weakens plants.
I have to say I was very disappointed with my mail order purchases. Roots were small and had very few signs of life. Though I planted them right after they arrived, only about half of them grew, and those that did were not the variety I ordered. I didn’t bother saving any of the roots.
I did, however, have success with the second part of my canna experiment.
I was able to find a generous selection of canna plants in the garden centers. Breeders have developed excellent seed strains that grow naturally bushy and full, and do not carry viruses. Until recently, seed cannas were short, growing only about 24 inches tall.
Since I want a taller plant for mid-garden, I was eager to try the latest new introductions. Last season I grew Cannova, which reaches four feet, and is available in Mango, Bronze Scarlet, Lemon, Rose, Red, Yellow and Bronze Orange. I’d like to find the South Pacific series this year, with flowers of Scarlet, Orange, Rose or Ivory, and height up to 52 inches. Plants start blooming at just over a foot tall and continue to bulk up over the season to their impressive, full height display.
Take advantage of the nice weather and get planting summer now.