Most of us are happy to bid adieu to summer’s oppressive heat and humidity, but we’re not ready to give up color in our landscape.  And no reason to.  This time of year nursery shelves are full of autumn color: mums, pansies, ornamental kales, grasses, and late blooming perennials. And a great way to keep color around is in container gardens.
Using plants in containers is a lot like accessorizing an outfit – you can go big, small, go bold, go monochromatic. And when you get tired of one look, it’s easy to change it up.  Start by giving the plants good home ground. Containers need good drainage to prevent the plants from sitting in water and rotting.
If you’re re-using soil from your summer pots, it will need to be refreshed; dump out about a third of the old soil and replace that amount with a nutrient rich soil amendment like Bumper Crop. If you’re starting fresh, good quality potting mix is essential.
Fill the container with soil, and water before planting; the soil will settle and you may need to add more. When fully planted, the container should not be packed to the brim; leaving a half an inch or so space below the brim will make it easier to water – and keep the soil in the pot.
When it comes to choosing plants, the possibilities, the combinations, the styles are limited only by your personal taste and imagination. For a clean look choose a single variety in pots that match. Shake it up and go for different sizes and colors of pots. Go bold and choose pots opposite the color wheel from the flowers –a cobalt blue pot planted with bright yellow sunflowers. Create a potted Cottage garden with pots in varying sizes and styles full of zinnias, snapdragons and ornamental grasses.
“Thrills, fills and spills” is a good design rule of thumb. Use a tall statement plant, like an ornamental grass or millet for the “thrill.” For the “fill” choose smaller, fuller plants like mums, pansies, or ornamental cabbage. The “spill” is a plant that hangs down over the side of the pot. A good choice for the cool season is hedera helix ivy. For Halloween fun, stick a small pumpkin or gourd in your arrangement.
As long as the pot is big enough to hold ample soil, just about any plant will survive in a container. Winter hardy perennials will come back next year: Sedum, Japanese anemone, purple ironweed are examples of fall-bloomers. For texture go for silver artemisia, tickseed, or an ornamental grasses. “Little Bunny” or “Hameln” pennisetum stay small and are good choices. Spice it up with winter hardy herbs like rosemary, thyme and oregano.
Venture further into the nursery for evergreen shrubs that will take a container garden through winter. Boxwood is a common choice, and come December a string of lights turns it into a festive holiday decoration. Up the formal factor with topiaries planted in iron urns. If you want a bit of color, under-plant with pansies. For a less traditional look, consider a dwarf nandina: “Firepower” or “Gulf Stream” combined with purple ornamental cabbage and a few pieces of green ivy is a smart grouping and will carry right through winter. A large pot planted with a red twig dogwood will make a striking architectural statement, especially when placed in front of a white or light color wall.
Think ahead to spring. Plant a “secret pot” of spring flowering bulbs like tulips, crocus, and hyacinth. Plant it now – and forget about it. That is until you spy green poking up through the soil. Put the pot in a sunny location, keep it watered and you’ll have spring on your doorstep.
There are as many choices when it comes to planters. Inexpensive terra cotta pots are fine for temporary seasonal or holiday decoration, but they will crack after a few freeze/thaw cycles. Thick ceramic, concrete, wood, metal, plastic, or fiberglass pots will stand up to Maryland winters. Have fun and think outside of the pot. Offbeat containers -– old watering cans, metal tubs, even an old pair of shoes – bring a whimsical personality to your potted garden.
Late season container gardens don’t require the daily watering demanded by their summer counterparts, but they’re not maintenance free. Keep tender annuals, like snapdragons, zinnias and sunflowers watered until they die off in freezing temperatures. Some like pansies and ornamental cabbage look great until we get heavy snow or ice. But winter hardy choices are alive and need light watering – once a week should do it – through the cold season. When you begin to see new green growth in early spring, wake them up with a liquid fertilizer like Daniel’s Organic or Miracle Grow…and you’re off and growing to another season.