Water containers thoroughly when the soil surface becomes dry to the touch. During the hottest part of the summer, this can mean watering every day. Water each pot until it drains from the bottom, wait 5 minutes and repeat to ensure that moisture has reached the deepest roots. Watering early in the day decreases the chances of foliar diseases. Using saucers will give overly dry soil a chance to wick up and absorb the moisture. Be careful using saucers under containers in shady locations or during rainy periods, as they can keep the soil too damp.
Many potting mixes lack organic matter and nutrients. Plants need a regular dose of fertilizer. A time-released fertilizer will slowly feed the plants for a few months. Because container plants are heavy feeders, about a month after planting also start feeding with water-soluble fertilizer. Since over fertilizing can be as bad or worse than no fertilizer, I usually use liquid fertilizer at half strength and apply it every two to three weeks through the season.
Deadheading faded blossoms and removing damaged or diseased leaves and stems not only keeps plants looking good but also keeps them productive and healthy. Deadheading redirects a plant's energy from seed production back into flower production. When snipping off blooms, cut flower stems back to a leaf node or main stem. Do not leave any unsightly headless or leafless stems.
Removing problem leaves back to the main stem is also important. If an entire stem is damaged or diseased, cut it back to the nearest healthy growing point or all the way back to the base. It's best to remove disfigured leaves and stems as soon as you notice them. Injuries attract insects and encourage diseases.
If a plant becomes less productive, cut all the stems back by as much as half, to a leaf node or growing point. Gradually pruning over a three week period, by cutting one-third of the stems back each week, could be less dramatic. Avoid pruning plants during the heat of the day, which is stressful for the plant. Prune them in the morning or evening while the stems are firm yet bendable.
