Whether you want to harvest vegetables from a window box, hang baskets of colorful flowers or add an accent to a tabletop using a dish of succulent desert plants, there are many houseplants with shallow roots that can be successfully grown in containers less than 6 inches deep. Water requirements in shallow containers vary by species and plant type.
Succulents for Shallow Pots
Many succulents – plants native to arid regions that store water in fleshy leaves – are ideal houseplants with shallow roots. Their roots are so shallow, in fact, that multiple species are often grown together in dishes. Examples include hen and chicks (Sempervivum spp.), also known as houseleeks, which grow in rosette form and have very fine roots that allow them to grow even in rock crevasses. Other options for succulent dish gardens are sedums (Sedum spp.) and echeverias (Echevaria spp.).
Another shallow-root succulent option for containers is the orchid cactus (Epiphyllum spp.), which produces brightly colored, orchidlike flowers. Orchid cactus grows better once its roots fill the container in which it is planted. The larger the container, the longer the orchid cactus will take to blossom, so planting in a shallow container is an advantage.
Fruits and Vegetables
Thanks to their shallow root systems, strawberries (Fragaria x ananassa) are easily grown in pots. You can grow strawberries in a shallow pot with a maximum width of 12 inches. For containers, consider day-neutral, or everbearing, strawberries. They are grown as annuals and don't need as much room to spread out as perennial strawberry plants.
Radishes (Raphanus sativus), bush beans (Phaseolus vulgaris) and greens are examples of vegetables that can be grown in 6 inches of soil, making them ideal options for a window box. For these kinds of vegetables, look for a gallon-sized container that is 4 to 6 inches deep. You can also plant celery (Apium graveolens) in containers, as it can grow well in pots that are just 8 inches deep.
Growing Herbs in Containers
Many herbs used in the kitchen are suitable for growing in shallow containers. One of the best herbs for container growing is parsley (Petroselinum crispum). Because of its shallow root system, you will need to fertilize and water parsley frequently. Space parsley plants 1 or 2 inches apart. If you would rather not have to remember to water your container herbs on a regular basis, consider Mediterranean varieties that can handle drier soils, such as rosemary (Salvia rosmarinus), oregano (Origanum vulgare) and thyme (thymus vulgaris).
Shallow-Rooted Flowers for Containers
Annual plants, which only live for one growing season, have shallow roots, which makes them perfect for planting in containers indoors. Consider small varieties of annual vinca (Catharanthus roseus), which come in shades of purple, pink and red as well as white and can handle droughtlike conditions. For containers, consider the 'Mediterranean Deep Rose' cultivar (Catharanthus 'Mediterranean Deep Rose'), which has magenta-colored flowers.
Other flowering indoor plants that do well in shallow pots include geraniums (Pelargonium x hortorum), pansies (Viola x wittrockiana) and creeping zinnia (Sanvitalia procumbens) to name just a few.
- HGTV: How to Grow Strawberries in Pots
- University of Minnesota Extension: Tips for Growing Strawberries in Containers
- University of Illinois Extension: Making Herb and Vegetable Containers
- HGTV: How to Grow Edibles in Window Boxes
- Kansas State University Extension: Parsley
- Better Homes & Gardens: 10 Plants that Grow Surprisingly Well in Containers
- University of Wisconsin-Madison Division of Extension: Growing Vegetables in Containers
- Better Homes & Gardens: Hens and Chicks
- Better Homes & Gardens: Annual Vinca
- Oregon State University Extension: Orchid Cactus - Epiphyllums
- Clemson Cooperative Extension: Hanging Baskets and Window Boxes