Lush and floriferous as your summer containers are, a fall container garden can do double duty and take you clear through winter.
A pretty container garden of flowers and foliage planted in the fall can be the star of the entranceway when the weather turns colder just by selecting the right plants for the season. Adding Christmas lights will make them even more festive and inviting during the holidays.
You could go simple. An upright Japanese holly in a pot and some variegated ivy to trail down the edges works wonderfully, especially with lights. To get a little more elaborate all you need is the basic container design formula known far and wide as: thrillers + fillers + spillers.
It’s pretty self-explanatory; you take a main central accent plant or plants (thrillers), fluff them up with some interesting shorter plants (fillers) and finish off your horticultural confection with some nice trailing plants (spillers). Select your plants so the colors and textures either coordinate or play off of each other and make sure they will all tolerate the same light and water conditions.
In fall, one has a more limited palette of plants to choose from since they must meet certain criteria, namely not getting frozen to bits when the temps dive below freezing. Evergreen plants such as ‘Yuletide’ camellia, dwarf arborvitae, dwarf false cypress, dwarf Alberta spruce, ivy topiaries, and nandina make excellent thrillers that can take the cold.
There are even a few standout plants that lose their leaves and yet have enough presence to make for a central accent. One such plant is Harry Lauder’s Walking Stick, a contorted filbert with lovely, twisted twigs you can drape with lights and miniature ornaments, not to mention cut for indoor arrangements.
Good fillers for fall containers include evergreen ferns, Lenten roses, sedge grasses, and spurges. Flower power is limited primarily to pansies and violas. Diascia and superbells (Callibrachoa) will sometimes get through a mild winter or at least take you through December, but only pansies and violas will come through winter and bloom through spring. They need several hours of sun to flower well. Other colorful accent plants include heuchera and dusty miller, as well as ornamental cabbage, kale and mustard. These have interesting foliage and texture and can often function as the centerpiece of a small container garden.
Which brings me to the next point—various thrillers and fillers can change roles depending on the size of the container they’re in. A nice burgundy ‘Redbor’ mustard might be the thriller in a 10-inch bowl, but becomes a filler in a larger container.
Spillers, though, are usually pretty much spillers unless they can be trained up a trellis, or a topiary frame. Good choices for trailing plants include ivy, creeping Jenny, vinca vine and variegated wintercreeper. Important tip: if you buy ivy in the fall for an outdoor container garden, make sure to buy it from the outdoor section of the nursery, not the greenhouse. Otherwise, the ivy may not be “hardened off” enough to go through winter undamaged.
There are a few potting and planting tips for success.
1. Always use bagged potting mix for container gardens rather than topsoil or soil dug from the ground. If you are planting shrubs and perennials, select a mix that is heavier in bark content.
2. Make sure your containers have drainage holes and keep the holes from losing potting mix by putting mesh screen over them before filling the pot with mix. Set plants in the pots so they sit at least one inch below the rim of the pot. Otherwise, watering will be difficult.
3. Once planted, water your container plants twice to make sure the soil mix settles completely. You may need to add more potting mix afterwards to fill in sunken areas.
Tina Mast is communications director at Homewood Nursery in Raleigh. She can be reached at firstname.lastname@example.org or 919-847-0117.