Hanging baskets and containers are used by almost every gardener I know to decorate porches, decks, and other outdoor landscape areas. Any container requires specialized care to ensure the flowers stay strong and look good throughout an entire growing season.
Watch water needs
When planting containers, soilless potting mixes are used. These mixes come in various forms, but they have the advantage of being weed, disease, and insect free if they are of good quality. These organic materials make a wonderful rooting medium for plants, but they also require close monitoring during hot summer conditions. Soilless potting mixes drain quickly and dry out much more rapidly than garden soil. Plants growing in containers also have a limited root system and so it is critically important to monitor moisture levels- especially as plants mature during the summer. Plants in containers may have to be watered more than once a day during peak times of wind and heat, while during cool overcast weather they may not require watering for several days.
Waiting too long to water is a common cause of plant failure. Many plants will not recover if allowed to wilt down excessively since this damages the water conducting system. Be sure to water thoroughly as needed so that water drains from the bottom of the container.
Fertilization
Container plants must also be fed regularly. The confined root system cannot go out in search of food, so it must be provided. Water-soluble fertilizers work well for containers. These can be mixed in water and poured into the potting mix. Fertilizers that are balanced make a good choice for containers. 10-10-10, 24-8-16, or 12-4-8 are just a few examples of common fertilizers that work well for containers. Some gardeners choose to lightly fertilize every other watering. If you do this use ¼ the label rate when you mix the fertilizer. There are also slow-release fertilizers that release nutrients in a container over a longer period of time.
Lack of nutrition is another common reason that container flowers start performing poorly during the summer. Nitrogen is a mobile nutrient is can be removed quickly from the potting mix with frequent watering. Replacing nitrogen is important to keeping annual flowers growing and blooming.
Deadheading/Pinching
Deadheading is often helpful to keep container flowers blooming well. Deadheading is the removal of spent flowers as soon as they begin to decline. Once an annual flower blooms and sets seed, it has completed its lifecycle. By removing spent blooms, the plant is unable to set any seed and so it continues to produce flowers. Removing the dead flowers also improves the appearance of the container. Pinching or pruning container plants is also occasionally required to help encourage more branching and keep them looking full. If a plant is too long or straggly, prune it back and maintain good fertilization as mentioned above to encourage a fuller look.
Plant failures
We all experience plants that just don’t grow like we had hoped in a container for various reasons. If a plant fails, get creative and fill the empty space with some small garden art, a different annual flower, or simply just wait and plant some fall flowers in the open space later in the season.
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