How to plant containers for patios and decks
The containers you are going to use for seasonal plantings should have at least one bottom hole for drainage. A layer of gravel in the bottom of the container is not necessary.
Fill the container with a lightweight, fast-draining soilless mix -- avoid heavy garden soil. Leave enough space between the top of the growing medium and the pot to make watering easy.
Very large containers can be partially filled with wood chips or empty plastic pots to conserve soilless mix. Generally, allow for at least 12 to 15 inches of growing medium and more if you plan to grow large plants in the pots. Separate the wood chips from the growing mix with landscape fabric.
I prefer using empty plastic pots placed upside down to fill container volume and save on growing medium.
• Gradually move houseplants outside to protected areas when temperatures remain above 40 degrees Fahrenheit. Prevent any damage to the plants by gradually acclimating them to the sun and outside growing conditions.
Start by putting them in a shaded location outside on warmer days and bring them inside when nights are predicted to be cold. Increase the time outside and exposure to sun over a period of ten days or so.
Large houseplants in plastic pots should be slipped into larger heavier pots to prevent them from falling over in the wind.
• Some of your shrubs may have grown unevenly, so prune back any errant branches to even out the shrub and encourage it to fill in more evenly. You can also gently prune back the new growth on your shrubs to encourage the development of a fuller plant. Lightly shear your formal hedges to neaten them up and train their shape. These hedges will likely continue growing and need to be pruned again for the best results.
• Tim Johnson is director of horticulture at Chicago Botanic Garden, chicagobotanic.org.