With a container garden, you can grow something even where space is limited, add instant “curb appeal” to your landscape, or just ease into gardening cautiously. And, of course, every container garden can also be a small contribution to the environment.
Size matters when picking out the container. A large pot for several plants is a better investment than several small pots with one plant each. Small pots dry out quickly, but larger ones seem stabilize by creating their own ecosystem. The material of the container affects its drying rate, too. A plastic, wooden (with liner), or glazed ceramic container will keep the soil moist longer than a terra cotta or concrete container, unless a liner is available.
If your chosen container does not have a hole in the bottom, some nurseries will drill one for you. The container will drain best if it is not sitting directly on a surface. Place it on smooth flat stones for elegant ‘legs’, on a tray holding pea gravel, or on a dolly with casters. Inside the container, add a sheet of porous landscape fabric, or an inch or so gravel or pot shards to keep the soil from leaking through the hole. Fill the container with good potting soil. Soil directly from the garden is too heavy.
Plan for the top of the soil to be an inch below the rim of the container after the plants are in.
Gardeners used to be concerned primarily with what looked pretty and survived in Houston, but now we also consider whether it supports wildlife, can be eaten by humans, and is not an invasive species. In warm weather and a sunny location, try basil, mint, perilla, lemon grass, or lemon verbena together with insect-attracting plants like pentas, salvias, black-eyed susan and coreopsis. In cool weather, you can plant chard, cilantro, parsley, arugula or dill together with poppies, calendula, nasturtiums, and paperwhites. Some of the herbs have varieties with showy purple or striped leaves. Thyme and oregano look nice draping over the side of a pot, and varieties of eggplant, chili peppers, and leaf lettuces are as attractive as any ornamental plant.
If you don’t want to change plants by season or prefer simplicity, consider planting a small or dwarf variety of citrus, apple, or fig in your container. Urban Harvest list ideal fruit tree varieties for Houston at http://www.urbanharvest.org/advice/fruitgardening.html. A selection of perennial Texas natives in a large container could include salvias, manfreda, Lindheimer muhly grass, coreopsis, winecup, switchgrass, and lazy daisy.
Synthetic fertilizers, among their other faults, cause a buildup of salts in the soil of the container. It’s another reason to use organics. Save some rainwater for your container garden. It will help flush out minerals left behind by tap water.
Mulch will protect the plant roots, just as in a garden bed. Look for hardwood mulch made here in Houston from local tree waste. For style points, you might try a layer of tumbled recycled glass in a container where plants are not changed often.
Now that the burn of summer is easing, a container garden is a good way to kick off the next planting season.
Mary Carol Edwards is a landscape designer and owner of Luminous Ground Design. She specializes in landscapes which unite the environment and architecture, and support natural ecology. She considers a landscape a success if it can do all that and be fun, elegant, and creative, too.