Growing great container plants
By Dawn Pettinelli - UConn Home & Garden Education Center
Featured Article - posted Wed., May. 16, 2012
Whether you are short on space, looking for ways to accentuate your house, porch or deck, or just enjoy their mobility, growing plants in containers is a rewarding gardening adventure. Plants can be grown in almost any type of container. Plastic and clay pots are quite ubiquitous, but there are more and more wonderful decorative cement and cement alternative pots, urns and troughs. Beautiful ceramic pots, crocks, iron kettles, wooden buckets, half whiskey barrels, hanging basket planters, upside-down pots and sacks, even an old wheel barrow can all be filled with colorful plants. You are only limited by your imagination.
One important factor to consider when choosing a container is drainage. Preferably, all containers should have drainage holes. This is especially important in growing season like last year’s with almost two months worth of rainy weather. Even though I put a layer of small stones on the bottom of my coal scuttle bucket, it began to fill with water and the roots of my prized red rosebud geranium were being submerged. I had to repot the plant and bring the container into the cellar when large amounts of rain were predicted. If you could drill holes, that would be a preferable option.
Wooden containers should be lifted slightly off the ground so water cannot collect under them. I use three bricks under my whiskey barrel. For wooden window boxes, consider planting in fitted liners so that the wood will not be in constant contact with moist potting medium. Alternatively, consider painting the inside of the box with a water-proofing material. While you can purchase window boxes made of weather-proof compounds, the wooden boxes give you the option of painting or staining the outside to match your house, and sometimes this is desirable decorating touch.
Like your choice of containers, the varieties of plants you can grow are quite varied. Medium-height, low-growing, and trailing plants are best suited to most containers and they fall into the modern categories of thrillers, spillers and fillers. The size of the plant really depends on the type of container used. As a general rule of thumb, the tallest mature plant should be not more than one and one half times the container height.
Annuals, vegetables, houseplants and summer flowering bulbs are all excellent candidates for container gardening. Visit your local garden center for lots of new tender perennials that might add just the touch that you are looking for. For sunny spots, try marigolds, petunias, alyssum, Madagascar periwinkles, portulacas, verbenas, dianthus, gazanias or nasturtiums. I have the bright orange, red and gold trailing nasturtiums planted in three window boxes on my deck’s railing. As the stems tumble down and produce softly scented vibrant blossoms, they are constantly visited by our local hummingbirds.
Many colorful plants will tolerate shady areas including impatiens, nemesia, lobelia, fuchsias, coleus, cineria, begonias, browallias and polka dot plants. If you have a kitchen window box, why not plant some herbs that will always be within reach for flavoring or garnish? Bush basil, tricolor or golden sage, rosemary, parsley and thyme are just a sampling of herbs easily grown.
Many compact vegetable varieties are suitable for containers. The smaller patio tomatoes, lettuce, bush or pole green beans, compact squash and melon varieties, peppers and eggplants all lend themselves nicely to container growing. Add a few annuals for color or an herb or two for flavor.
Summer flowering bulbs such as tuberous begonias, dahlias, fairy lilies, ornithogalum, caladiums, cannas and calla lilies also add a delightful spot of color to any area.
Commercial, soilless, sterilized potting mixes are a good choice for container gardening. They are light-weight and drain well. Because of the frequent watering, nutrients are readily leached from the medium. Whether using natural organic or synthetic fertilizers, it is a good idea to fertilize every other week with a water-soluble fertilizer. Alternatively, slow or time release fertilizers may also be used. If plants look hungry in July, either reapply the slow or time release fertilizer or start using water-soluble ones. Water whenever the soil feels dry, which may be every day during hot, sunny weather. To prolong the blooming period for flowering plants, remove dead blossoms and seed pods.
Container gardening provides all the rewards of regular gardening but usually with less work than planting in the ground. If you have questions on container gardening or on any other home and gardening topic, call, toll-free, 877-486-6271, visit the website at www.ladybug.uconn.edu, or contact your local Cooperative Extension Center.