Top-quality potting soil, experimentation are key

Here are some tips from Jeff Epping, horticulture director at Olbrich Botanical Gardens in Madison, Wis.:

Fill your flowerpots with good, brand-name potting soil.

You do not have to throw away the potting soil in your pots every year. In his garden at home, Epping mixes old and new potting soil. “I sweep the garage floor, empty the containers, and then I just mix in new potting soil and shovel it into the pots.”

Some potting soils include added fertilizer or moisture-retaining crystals, but you’ll still need to water and fertilize. A slow-release fertilizer may also have to be supplemented with occasional water-soluble fertilizer. Look at your plants, Epping says. “They should always be growing. When they stop growing, they are starving.”

Water thoroughly. “ Everyone wants to give their plants just a little sip,” Epping says. “Water until it comes out of the drainage hole.”

Plant densely, and let plants lean on each other and grow together in their pots, just as they would in a garden bed.

Experiment: Epping planted some small, scraggly pine trees from a garden shop (he paid $3 each) in pots in his own garden, and pruned them to look like bonsai. “I’ve had them for four years, and I love them,” he says. He grows low sedums around the little trees.

Don’t abandon reliable plants that work for you. “It’s hard to beat petunias,” Epping says.

If a plant isn’t thriving, pluck it out. “If it looks like heck, tear it out and put something else in,” Epping says. “Do yourself a favor.”