Inverted gardening challenges the typical understanding of how plants interact with their environment by securing the roots above and allowing the foliage to grow downward. While this method may seem counterintuitive, it is a practical technique with a basis in plant science. The feasibility of this unconventional approach is rooted in the plant’s inherent biological programming.
The Short Answer: Yes, But How?
Growing plants upside down is possible using a specialized apparatus that holds the plant in an inverted position. This technique bypasses the need for traditional in-ground planting beds or standard upright containers. The primary requirement is a sturdy, suspended container, often a bucket or commercially designed planter, filled with growing medium.
The plant’s root ball is secured inside the container, with the stem and foliage fed through a small opening cut into the bottom. The container is then hung from a strong support structure, such as a sturdy hook or a pergola. This setup secures the root system and soil above, while the main stem emerges downward into the open air. The success of this method does not rely on the plant’s acceptance of the downward orientation but on its ability to reorient itself once established.
Understanding Plant Orientation: Gravitropism vs. Phototropism
The plant’s ability to correct its position after being planted upside down results from two fundamental biological responses known as tropisms. The first is gravitropism, the plant’s growth response to gravity. Plant shoots exhibit negative gravitropism, growing away from the pull of gravity, while roots show positive gravitropism by growing toward it.
Specialized cells within the plant, called statocytes, contain dense starch grains, or statoliths, that shift in response to gravity’s pull. When the plant is inverted, these statoliths trigger a redistribution of the plant hormone auxin, causing the cells on the underside of the stem to elongate more rapidly than those on the top. This differential growth causes the stem to curve upward in a U-shape, effectively defying the inverted planting position. This upward curve also aligns the foliage toward the light source, demonstrating the second mechanism: phototropism.
Phototropism is the plant’s growth response to light, and shoots exhibit a positive phototropism, actively growing toward the light source for photosynthesis. In an inverted garden, the shoot’s strong negative gravitropism and positive phototropism work together to ensure the stem bends and grows toward the sun. This dual mechanism ensures that the plant’s leaves can quickly position themselves to absorb sunlight, overcoming the initial disorientation caused by the unusual planting angle.
Ideal Candidates and Practical Setup
The most successful candidates for inverted gardening have a naturally vining or trailing habit and a relatively shallow root system. Popular choices include tomatoes (especially smaller-fruited cherry or grape varieties), peppers, eggplants, and strawberries. Vining cucumbers and many herbs, such as basil and mint, also adapt well. Plants that produce very heavy fruit, like large beefsteak tomatoes or squash, may struggle as the weight can stress the stem or the planter itself.
Setting up an inverted planter requires careful attention to the small opening through which the plant stem is inserted. The hole must be large enough to accommodate the stem without crushing it, but small enough to prevent the soil mixture from falling out. Before hanging the planter, the roots must be protected, often by wrapping the root ball with fabric before pulling the stem through the hole. The container should then be filled with a lightweight, well-draining potting mix that will not compact easily.
Watering is a unique consideration because gravity pulls water rapidly downward, leading to quicker drainage. The soil reservoir should be checked daily, and in hot weather, it may require watering twice a day to prevent the roots from drying out. Applying a liquid fertilizer is often more effective than granular fertilizer, as the liquid is carried directly to the roots by gravity during watering. The planter must be hung from a structure that can safely support the full weight of the container, wet soil, and a mature, fruit-laden plant, which can easily exceed 40 pounds.
Unique Advantages of Inverted Gardening
The inverted orientation offers several benefits over traditional in-ground planting. Since the plant’s foliage and fruit never touch the soil, it eliminates many common ground-dwelling pests like cutworms, slugs, and snails. This physical separation also greatly reduces the risk of soil-borne diseases, such as certain blights, from splashing up onto the lower leaves during rain or watering.
This method maximizes space, making it highly effective for urban gardeners, apartment dwellers, and those with small balconies by transforming unused vertical space into a productive garden area. The downward growth of the plant also makes staking and caging unnecessary, as the container’s suspension supports the structure. Furthermore, the elevated position means the soil is contained entirely within the planter, which eliminates the need for weeding and prevents the growth of competitive plants.