There are a lot of reasons to choose to garden in containers. Containers can be decorative masonry with lacquered colors   or they can be the classic red clay flower pots. Other options include half whiskey barrels, black or colored plastic, hanging baskets, and even wooden and natural fiber troughs or trays.  All containers require drainage holes and potting mix. A bagged potting material without soil is best to use because of drainage, disease, and pH concerns.  Such a potting mix has almost no fertility. The gardener is the sole source of nutrients. Use Osmocote or a similar slow release product applied once every year supplemented by a soluble fertilizer such as Peters or Miracid dissolved in the irrigation water on a regular basis.

Gardening in a container allows you to grow plants such as blueberries, hydrangea and gardenias that require acid soil.  Acid loving plants don’t last long in our alkaline soils.  Create an acid soil in a container. I by mixing a potting soil 50-50 with sphagnum peat moss.  The sphagnum peat moss is very acid and that acidity dominates the soil reservoir in the container as the sphagnum decomposes. Enhance the acidity by using rainwater to irrigate and Miracid to fertilize the acid-loving plants in containers.  Like the potting mixes, sphagnum peat moss is nutrient free so the Miracid water soluble fertilizer is very important.

Container gardening is an efficient way to grow herbs for cooking. A two or three gallon container is an ideal size to grow one specimen of most herbs, and one plant is often the right number of plants of a particular herb that is needed to meet the families cooking needs for that herb.  Want more cilantro or sweet basil, then grow two 2 gallon containers instead of one.  Seven to 10 containers of herbs such as parsley, rosemary, thyme, cilantro, dill, fennel, sage, oregano, mint, chives, and basil make an attractive, complete container garden. Parsley, dill, and cilantro grow best in the winter in Central Texas. Basil, thyme, mint, and oregano are summer herbs.   Full sun is best but most of the herbs listed will be adequately productive in morning or afternoon sun. One of the best arguments for growing the herb garden in containers is that it can be grown close to the kitchen for easy care and harvest.

The same arguments supporting the idea of an herb garden in containers can be made for using containers for vegetables. Peppers make handsome specimens in containers and can be very productive in a 5 gallon container in the summer. Grow a spring and fall crop of tomatoes in 10 gallon or larger containers. One key is to select the right varieties. Use determinate tomato selections such as Tycoon, Celebrity, Red Deuce, and BHN 958 that grow quickly to full size and produce their fruit.   Avoid the indeterminate varieties that grow to 8 feet tall. Cucumbers are also a productive summer vegetable. In the winter plant a selection of the different colored leaf lettuces or “Bright Lights” chard. Green onions, carrots and radishes are also easy and fun to grow.

Gardening in a container limits the size of some desirable but normally large plants that require cold weather protection. The smaller size plants are easier to protect from cold.  Backyard citrus can be an attractive, productive part of area landscapes. Its limitation is that some of the most desirable varieties, Meyer lemon and Mexican lime, are cold sensitive enough to require protection several times per winter. If you grow them in a half whiskey barrel they only grow to 3 feet tall and 4 feet around. You still have the evergreen foliage, fragrant blooms, and abundant fruit plus they are small enough to cover with agricultural fiber or blankets with the expectation that the plants will survive.  Some gardeners even outfit the barrels with wheels so the plants can temporarily wheeled into the garage until the freezing temperatures end.  The wheels can also be used to move the plants from one sunny spot to another in predominantly shady landscapes.

Containers are consistent with Mexican courtyard themes and allow gardening on a patio. Tropical flowers such as bougainvillea, oriental hibiscus, and mandivillea are mainstays of decorative plantings for large hanging baskets and containers on courtyards and patios in full sun. Firebush can be very interesting as well. It has attractive foliage, blooms in late summer and seems to be the favorite hummingbird nectar source. If you have a firebush in a container on your patio, expect the migrating hummingbirds to entertain you as they squabble over possession of the nectar producing plant. . Grow firebush in 3 to 5 gallon containers.  For smaller containers in the sun, decorate with moss roses and the small zinnias. Pentas are hard to beat for color in the shade. Select from red, pink, white, or lavender. In the winter grow snapdragons, stocks and pansies in containers in the sun. In the shade cyclamen and primula are spectacular container plants.

Written by Calvin Finch
Dr. Calvin Finch is the retired Urban Water Program Director for the Texas A&M Institute of Renewable Natural Resources.You can ask Calvin question and hear his answers on the air as he co-hosts the Gardening South Texas on the air at KLUP (AM 930) Saturday and Sunday from 12:00 to 2:00pm.