Lengthen your season, extend your enjoyment, and experiment!
The three elements of container design—often called “Thrillers”,“Spillers”, and “Fillers”—make for an interesting and balanced container. Combine a tall upright plant, a cascading plant that spills down the pot’s sides, and a filler to add fullness and color. Plant early spring annuals this spring to extend the container season. With these cool weather annuals you can plant your container in mid-April instead of waiting until mid-May! Cool weather annuals, which have been hardened off, will survive the light frosts of late April and push the envelope of your planter’s performance and your enjoyment of it as well.
Osteospermum and Argyranthemum are both vigorous, upright plants with striking daisy-like flowers, exceptional compact habit, and branching that makes them ideal for both containers and landscapes. Plants grow 10 to 18 inches high by 12 to 24 inches wide. You can also use early blooming bulbs such as Daffodils, Fritillaria, or Tulips as your upright element and then fill in with a new “Thriller” after the bloom fades. (Think of your planter as your laboratory where you can experiment on a small scale with color and plant combinations. Have fun. Isn’t that what gardening is all about?)
Osteospermum the Zion series is an eye-catching hybrid with large flowers and an array of unusual bloom colors. We are looking forward to Zion Copper Amethyst, Zion Orange, and Zion Pink Sand—their names describe them as well as I can, one intense color gradating into another along the pedal. Truly stunning!
Argyranthemum grow slightly larger than the Osteospermum. They are part of the aster family and so offer a little more of a cottage garden aesthetic. They are heat and cold tolerant and several new varieties are available this year including a fully double, blood red variety called Madeira Crested Merlot and a romantic, antique pink variety called Madeira Crested Violet.
Diascia and Nemesia also bloom all season long, but perform best in the spring and fall, and appreciate a little shade during the heat of summer. We also recommend shearing these plants mid-season to improve their performance. Plants grow 8 to 12 inches tall and wide.
Nemesia Serengeti Upright White is one of our favorite varieties. The upright habit shows off the multitudes of delicate white blooms with yellow and purple inner accents.
Your planter will bring a smile to your face all through the spring. Then in July, if any of the cool weather annuals such as Diascia and Nemesia are not performing as well in the heat, remove them (you can plant them in a shady spot in your garden and they will revive and flower through the fall) and replace it with a heat loving “Filler” like Euphorbia Diamond Frost.
Calibrachoa, Bacopa, and Petunias are cascading plants that perform from the cool early spring all through the season to the end of October.
Calibrachoa are early flowering, brilliantly colored, petunia-like flowers, which self-deadhead and grow in full sun or part shade. Often called “Million Bells” because of their profusion of blooms, they are heat-tolerant and stay compact and bushy even when they are stressed. The variety we are looking forward to the most is Double Amethyst: a new amethyst-blue variety. We can’t wait!
Bacopa is also a heat-tolerant, abundant flowering cascading annual covered in cheerful, stout, five-pedal flowers. We love it in white, because of its versatility, but it is also available in pink and blue. Besides being a sturdy and well performing container plant, we have experimented with this annual in the garden. When planted in the ground Bacopa becomes an adorable semi-mounding ground cover.
Petunias were your grandmother’s favorite for a reason! Petunias perform in dry hot sun, in cool shade, in containers, in the garden. I have seen petunias self-seed themselves into cracks in concrete or asphalt! These flowers are tough as well as beautiful. This year we are looking forward to Pretty Much Picasso, and Phantom, these are not your standard ho-hum varieties!
by Kerry McQuaide from Victoria Gardens in Rosendale, NY