The trash can gardening method offers an accessible solution for cultivating a substantial potato harvest, particularly in urban environments or smaller spaces. This technique utilizes vertical growth to maximize yield, allowing tubers to form at multiple levels along the developing stem. A significant advantage of this container system is the simplified harvest, which eliminates the strenuous digging normally associated with in-ground potato beds.
Preparing the Container and Seed Potatoes
Selecting an appropriate container, such as a 20- to 32-gallon plastic trash can, is the first step. Proper drainage is paramount; several half-inch holes must be drilled into the can’s bottom and lower sides to prevent root rot. The can should also be thoroughly cleaned to ensure no toxic residues remain.
Preparing the seed potatoes involves chitting, which encourages sturdy sprouts before planting. Place seed potatoes in a cool environment (50–55°F) with indirect light for four to six weeks. Orient the potatoes with the “rose end,” which contains the most “eyes,” facing upward to promote robust sprouts.
Larger seed potatoes can be cut into pieces, ensuring each section contains at least two or three eyes for viable growth. These cut pieces need a curing period of one to two days in a dry location to allow the exposed flesh to form a protective, calloused layer. This seals the cut surface against soil-borne pathogens and reduces the risk of rot. The initial growing medium should be a loose, well-draining mix, such as potting soil and compost, placed in the bottom of the can to a depth of four to six inches.
The Planting and Hilling Process
The prepared seed potatoes are planted directly onto the initial layer of soil, spaced about 10 to 12 inches apart. After planting, cover the tubers with three to four inches of the same light, well-aerated soil mix. The soil should be gently firmed but never compacted, as potatoes require a loose medium for tubers to expand freely.
The technique of “hilling” is central to this method and must be performed repeatedly to encourage greater tuber production. Once green shoots emerge and reach six to eight inches above the soil, add more soil mix around the stems, covering all but the top few inches of foliage.
Potato plants form new tubers (stolons) along the buried portions of the main stem. Continually burying the stem creates more growing space for potatoes to form in layers. Repeat the hilling process every time the plant grows another six to eight inches, continuing until the soil level reaches near the top rim of the trash can.
Ongoing Care and Troubleshooting
Potatoes in containers require diligent watering because the confined soil mass dries out quickly. Maintain consistent moisture throughout the entire depth of the can, but the medium must never become waterlogged, which leads to fungal diseases and tuber rot. Aim for about an inch of water per week, increasing frequency during hot weather and when the plants begin to flower.
The plants need full sun—at least six hours of direct sunlight daily—to support tuber development. Container roots can overheat, especially in dark plastic cans exposed to intense sun, causing stunted growth. Insulate the roots by placing the can in a partially shaded spot during the hottest part of the afternoon or by covering the exterior with a light-colored material.
Common issues like the Colorado potato beetle or early blight can occur. Blight, a fungal disease, is exacerbated by moisture on the leaves, so direct watering at the soil level to keep foliage dry. Regular inspection allows for early manual removal of pests, which is effective in a small-scale container garden.
Harvesting Your Potato Crop
The plant signals harvest time when the foliage begins its natural senescence, turning yellow, wilting, and dying back. This dieback means the plant has finished producing energy and is maturing the tubers underground. At this point, cease watering entirely for about two weeks to allow the potato skins to thicken and harden.
This drying period, known as “setting the skin,” makes the potatoes more resistant to damage and improves storage life. The trash can method simplifies the final step, as the entire contents can be tipped out onto a tarp or wheelbarrow, allowing the potatoes to be easily sifted from the loose, dry soil mix.
After harvesting, the potatoes need to be cured for approximately two weeks in a cool, dark, and moderately humid environment (55°F to 60°F). Curing allows minor bruises to heal completely, preventing moisture loss and prolonging shelf life in long-term storage. Do not wash potatoes until immediately before use, as surface moisture encourages spoilage.