A potato tower is an innovative gardening technique that maximizes yield by growing potatoes vertically in a confined space. This method is especially beneficial for urban gardeners or those with limited yard space because it capitalizes on upward growth rather than horizontal rows. The core principle involves continuously adding growing medium around the potato plant’s stem. This encourages the plant to produce tubers along its entire buried length, significantly increasing the harvest. The vertical structure also simplifies the labor-intensive process of harvesting, allowing for easy retrieval of mature potatoes at the end of the season.
Choosing Materials and Location
Selecting the right materials and site is the first step for a successful potato tower. The structure can be built from various materials, including a wooden box with removable sides, a cylinder made from welded wire mesh, or a large fabric grow bag. A wire mesh tower should be at least 18 to 24 inches in diameter and three to four feet tall to provide adequate space for multiple layers of growth.
The growing medium must be light, loose, and well-draining to prevent waterlogging and allow for tuber expansion. An ideal mixture includes aged compost, loose garden soil, and a component like coconut coir or peat moss for drainage.
For the seed potatoes, choose certified, disease-free stock. Indeterminate varieties, such as Russets or Kennebecs, often perform better in towers because they produce tubers along the stem as it is covered. The tower’s location requires full sun exposure, meaning a minimum of six to eight hours of direct sunlight daily, and should be on level ground for stability.
Step-by-Step Construction Guide
Construction begins by forming the chosen material into a stable, vertical container. If using wire mesh, cut a section 10 to 12 feet long and three to four feet high. Bend this section into a cylinder and secure the ends using zip ties or wire. This size ensures the cylinder is wide enough for a healthy root system and accommodates multiple layers of growth. For stability, drive three or four wooden stakes or rebar posts into the ground around the perimeter, securing the wire to them.
Lining the interior of the wire structure is important for maintaining soil integrity. A layer of straw, hay, or cardboard can be placed along the inside walls to prevent the loose soil mixture from washing out through the mesh. This lining also helps retain moisture within the growing medium. Ensure the base sits firmly on the ground to establish the starting layer for the first set of seed potatoes.
Planting and Vertical Care
The first step in planting involves adding a six-inch base layer of the prepared soil mixture to the bottom of the tower structure. Place the seed potatoes onto this soil layer, spacing them four to six inches apart with the eyes or sprouts facing upward. Cover these seed potatoes with a thin layer of soil, followed by a layer of straw or hay to help retain moisture and prevent compaction.
Once the potato plants sprout and the stems grow six to eight inches above the soil line, the process of “hilling up” begins. This involves adding more growing medium, such as a mix of compost and soil or straw, around the stems until only the top few inches of foliage remain exposed. Covering the stem encourages the plant to produce new tubers along the buried portion.
Repeat the hilling process every time the plant reaches another six to eight inches of vertical growth until the tower is completely full. Consistent watering is important in vertical towers, as the upper layers can dry out quickly. Water deeply to ensure moisture reaches the lowest layers of the cylinder.
Harvesting the Tower
Knowing when to harvest involves observing the natural life cycle of the potato plant. The primary indicator is when the plant’s foliage begins to yellow, wither, and die back. This natural senescence signals that the plant has finished directing energy toward foliage production and has fully matured the tubers underground. Once the foliage has died back, leave the potatoes in the tower for one to two weeks before harvesting; this curing period allows the skins to toughen and improves storage potential.
Harvesting from a tower is simpler than traditional digging methods. For wire mesh towers, the structure can be tipped over and the contents spilled onto a tarp, allowing the potatoes to be easily sifted from the growing medium. If a wooden box was constructed, the removable slats can be taken off one by one from the bottom, exposing the mature potatoes in each layer. The soil and straw mixture can then be reused in compost or for mulching other garden areas.