For complementary (hot and cool) color combinations, chartreuse and hot pink or purple is a favorite combination, as is orange and blue or purple. Think vanilla-scented purple heliotrope and lime green creeping jenny or sweet potato vine or orange verbena with purple/blue salvia.
A monochromatic container holds different plants with flowers in the same hue. Red celosia, pentas, zinnias and trailing red verbena would be an eye-catching combination for a sunny spot.
Combinations of three are considered visually appealing. The phrase "thriller, filler and spiller" helps some gardeners to remember the tried-and-true combination of a tall eye-catching plant (the thriller), a midsize full plant (the filler) and a trailing plant (the spiller).
The dramatic New Zealand flax, which Mills describes as "yucca on steroids," comes in pinks, reds and maroon and would draw the eye upward in the back of a large container.
For a practical and attractive touch, include vegetables and herbs in your flowerpots. Swiss chard, lettuce, radishes, carrots and kales are tasty additions. Soft green sage leaves, ferny dill, ruffled parsley and spiny rosemary are useful as well as attractive.
For a simpler look, don't worry about combining plants. One large plant or several of the same kind create a colorful splash. I've been known to transplant a thriving hanging basket into a large pot for instant results.
Group single-plant pots together for more impact.
"A line of potted boxwoods along a walkway is very effective," said Mills.
The work isn't over once the plants are in the pots. There's the watering, of course, but also fertilizing. It's a step many people skip, but the results are undeniable. They might not be quite as dramatic as the "with" and "without" comparison photos in fertilizer advertisements, but applications do make a difference.
"Anything in a pot needs fertilizer. The water flushes the nutrition out," said Mills, who uses liquid kelp and fish emulsion on his containers. "Just don't apply it right before a dinner party. It does stink."
Chemical fertilizer labeled for use on blooming plants should produce more flowers.
If the plants you brought in before the first frost last fall survived the winter indoors, it's time to bring them back outside where they'll be happy to breathe the fresh air and soak up the sun. Minimize shock to plants weakened by a winter indoors by introducing them slowly to the outdoors.
"Put them in a sheltered place with morning sun for a few days before moving them into sunnier spots," said Mills. Don't place them outside at first on a windy day, or they'll be wind damaged. "Plants get burned just like we do."
If you suspect you might not remember the care instructions for your new plants, keep the informative plant tags as a reference. Or take a photograph of the tags on a smartphone so they'll always be at hand.
Mills recommends photographing the pots as well.
"That way, you don't have to try to remember what was successful and what wasn't from year to year," he said.
Reach Julie Robinson at email@example.com or 304-348-1230.