Pros and Cons of the Hydroponic Wick System

Perhaps the most popular hydroponic system among hobbyists is the wick system.

Not all hydroponic systems are the same. There are many different ways to grow plants without soil and many different ways to deliver a nutrient solution to the plant’s roots. One primary classification of a hydroponic system is whether the system is active or passive.

Active hydroponic systems require mechanical intervention from pumps, fans, or other powered devices to deliver the nutrient solution to the roots. Passive hydroponic systems, like the wick system, do not require a mechanical device to deliver the nutrient solution to the plant’s roots.

The wick system, like all hydroponic systems, has advantages and disadvantages. Examining the pros and cons of a particular hydroponic system is the best way for a grower to determine if it is ideally suited for his or her garden.

How a Hydroponic Wick System Works

Wick hydroponic systems rely on capillary action, which is the tendency of a liquid in a capillary tube or absorbent material to rise or fall as a result of surface tension and without the assistance of any force, like gravity. In fact, quite the contrary, capillary action allows a liquid to travel against the force of gravity.

Capillary action occurs because of the intermolecular force between the liquid and the surrounding solid surface. In the case of a wick hydroponic system, the surrounding solid surface is the “wick.” The combination of surface tension and the adhesive forces between the liquid and the wick material is what allows the liquid to travel against the force of gravity. (Read also: A Gravity-Fed Home Hydroponic Garden System)

Employing the phenomenon of capillary action, a wick system draws the nutrient solution up from a reservoir to the roots of the plants. The planting containers are normally placed just above the reservoir and are connected to the reservoir by wicks, which are submersed in the reservoir’s nutrient solution.

Typically, wick hydroponic systems use multiple wicks per plant (depending on the size and type of plant) to deliver the appropriate amount of moisture/nutrients. The distance between the growing containers and the reservoir is generally kept to a bare minimum. This helps maximize the efficiency of the wick system.

Advantages of a Wick Hydroponic System

One of the biggest advantages of a wick hydroponic system is simplicity. Without the need for mechanical devices, this system automatically eliminates many of the components that could potentially break down or require maintenance. Wick systems do not require specialized equipment and can be easily and inexpensively constructed with supplies from home, a local garden store, or a hardware store.

Many growers choose a wick system for its straightforward design. Since mechanical pumps are not necessary, a wick system uses less electricity than most hydroponic systems making them compatible with off-grid or remote locations where electricity is not available. Generally, wick systems also consume less nutrients than other types of hydroponic systems. This increases overall efficiency and makes wick systems an environmentally friendly choice.

The simplistic design, combined with the fact it can be built from repurposed and/or recycled items, makes wick systems one of the more affordable hydroponic systems available. In fact, they are a great starting system for any grower looking to experiment with hydroponics without making a huge investment.

Many DIY wick systems involve little more than buckets and/or recycled two-liter bottles for the reservoir and growing containers. (Read also: The Dutch Bucket Hydro System and How it Works)

As far as the wicking material goes, a specific horticultural wicking material works great, but any absorbent material, such as string, rope, yarn, or even strips of old cloth, will do the trick. In other words, many growers already have the components for a basic DIY wick system lying around their houses.

Disadvantages of a Wick System

Arguably the biggest disadvantage of a wick system is the limitation on the type and/or size of plants that can be grown.

Just about any type of plant can technically be grown in a wick system, but smaller plants, such as lettuce and herbs, tend to perform the best. This is partly because of the speed at which the capillary action delivers the nutrient solution to the root zone. Larger plants requiring more water and nutrients can be difficult to grow in a wick system because of its inability to provide an adequate amount of moisture/nutrients quickly.

Using multiple wicks and experimenting with different media can go a long way toward successfully growing larger-sized plants in a wick system. However, there are other hydroponic systems that are more compatible with growing large flowering/fruiting plants. (Read also: How to Build a Deep Water Culture System at Home)

Another disadvantage of wick systems is the potential for nutrient build up in the medium and the wicking material. Unlike hydroponic systems where the solution flushes the medium or can be quickly changed out entirely, the wicking material and the medium have the potential to hold some of the nutrients.

Nutrient build up can cause a series of problems in a hydroponic system, including erratic pH fluctuations, and nutrient lock out. Usually this can be avoided by a regular flushing of the medium and/or periodically changing out the wicks.

Additional Tips
Although one of the biggest advantages of a wick system is it doesn’t require electricity or mechanical parts, many growers still choose to include an air stone/diffuser (powered by an air pump) in the reservoir. An electric air pump teamed with an air diffuser/air stone will help add dissolved oxygen to the solution. Roots in hydroponic systems need access to oxygen in order to remain healthy and ward off potential pathogens.

Wick systems are one of the most straightforward types of hydroponic systems available. These systems are a great starting point for novice hydroponic growers who want to try their green thumbs at hydroponics. There are many DIY designs available online and, in most cases, a wick system can be built from recycled supplies already lying around the house.

Like most hydroponic gardening, experimentation is the best way to see what works and what doesn’t in a grower’s particular indoor garden. A basic understanding of the way wick systems work, along with a look at the advantages and disadvantages, will help give a grower the confidence to experiment with a wick system in his or her garden.