The Benefits of Using Wicking Beds in Your Garden

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Whether you have a well-honed green thumb or you’re just starting out in the world of gardening, your internet research has led you to stumble across this article. You may not have even heard of wicking beds before, let alone the benefits. Are they the answer to your perfect garden?

A wicking bed is a raised bed that is built on top of a water reservoir. The reservoir makes use of rainwater and provides water to the plants from the roots up, meaning a wicking bed is essentially self-watering. Wicking beds are most beneficial in arid climates with sparse rainfall.

Like all gardening methods, wicking beds will have their pros and cons. Whether or not you decide to opt for them is a personal decision and, since wicking beds are designed to be long-lasting, one you may reap the benefits of for several years. Keep reading to learn more about the benefits of wicking beds in your garden, and to decide whether they are worth it for you.

The Benefits of Wicking Beds

As the invention of a humble Australian engineer, wicking beds have become hugely popular within the gardening community. There is a reason for their popularity and a number of benefits to using wicking beds to grow your plants. The benefits listed below should help you to decide whether wicking beds are the right option for you.

They Save Water

Wicking beds were first thought of in the 1970s by an Australian engineer named Colin Austin; after a trip to Africa, he realised that famine could partially be attributed to arid climates, since there wasn’t enough rainfall for crops to grow.

Austin therefore sought to develop a gardening method that used very little water and, thus, wicking beds were invented. This reason also happens to be one of the biggest benefits of wicking beds.

There are two main ways in which wicking beds can save water.

  • Water is absorbed through the roots via osmosis, so they receive the most nutrients.
  • Evaporation from the top layer of soil is minimal to non-existent; because water comes from below the soil, the top layer remains fairly dry.

It’s thought that wicking beds use up to 50% less water than other gardening methods, which is why it’s such an effective option for countries with less rainfall. Additionally, the lack of water wastage will be attractive for environmentally conscious gardeners.

They Need to be Watered Less Often

Since the water reservoir makes use of rainwater, wicking beds don’t need to be manually watered nearly as often as other gardening systems. Indeed, they can go anywhere from a few days to several weeks between watering sessions.

If you don’t have the time for a garden that requires a lot of attention, then wicking beds might be the option for you. Additionally, you won’t have to pester your neighbour to water your plants if you go on vacation.

Wicking beds will be an attractive option for those living in high-rise apartments with balconies too. Since they are watered from the bottom up, they will not have the problem of water run-off.

There Will Be Less Weed Growth

Weeds tend to thrive in wet soil that doesn’t drain well. Drawing water and nutrients from the soil, they will multiply and interfere with the growth of your plants. If they are not taken care of, weeds can quickly suffocate your garden and undo all of your hard work.

Since the top layer of soil in a wicking bed is relatively dry weeds find it much harder to germinate, let alone grow. Once again, this is perfect for those who don’t have a lot of time to spend on garden maintenance.

They Can Be Placed Near Trees with Large Roots

Normally, trees such as willows and maples have invasive roots that spread far underground, meaning they use up the vast majority of water within the soil.

Since the wicking beds are raised above the ground and do not take resources from the natural soil, they can be used to grow plants in an area that might not otherwise be feasible due to the presence of invasive trees.

They Drain Efficiently in the Rain

Originally, wicking beds were designed so that areas with little rainfall could still grow crops. However, this does not mean that they won’t also work in wetter climates. In fact, their design naturally lends them to work well in a rainstorm.

All wicking beds should contain an overflow pipe (here is a diagram that shows this well) that drains excess water from the reservoir. This prevents the soil from getting waterlogged in a downpour, meaning that wicking beds can still thrive in heavy rainfall.

They Will Thrive Both Indoors and Outdoors

No matter your living situation, wicking beds should be a feasible gardening option for you. Not only can they be built at various sizes but they are also designed to be airtight so that, if a wicking bed is made correctly, there is no risk of flooding.

A wicking bed can be placed anywhere, be it a greenhouse, patio, or regular patch of grass.

They Will Protect Your Plants

This is a benefit shared by wicking beds and raised beds in general (you can choose to place an in-ground wicking bed, but generally they will be raised).

Surrounded by a wooden structure, your plants are safe from animals who manage to slip through the fence. You also won’t have to worry about warning your friends and family to steer clear of the garden.

They Allow Root Vegetables to Thrive

One of Austin’s other reasons for inventing wicking beds was that to enrich the western diet with more nutritious foods, after his wife developed Type 2 diabetes.

This is why wicking beds incorporate a bottom-up watering system so that the roots get the maximum amount of water and nutrients.

Since a wicking bed affords much more water to the plant’s roots than other gardening systems, it’s a brilliant option for growing root vegetables such as carrots, radishes and turnips.  These particular crops will thrive better in wicking beds than anywhere else so, if root vegetables are what you will be growing most often, consider this method.

They’re Easy to Use For Those with Mobility Issues

A wicking bed should be around 70cm high to allow for deep enough soil, or around waist height for the average person. This means that this gardening method does not require a lot of leaning over or other excessive movements. Wicking beds should therefore be ideal for those who want to get into gardening but struggle with their mobility.  

Additionally, since wicking beds don’t need watered very often, you will spend less time hauling heavy watering cans around your garden.

You Won’t Waste Fertiliser

This is another benefit that arises from not doing top watering, which will often flush fertilisers out of the soil.

In a wicking bed, fertiliser can be added directly to the reservoir. It is then absorbed by the soil exactly the same as the water. Not only will your plants thrive, but you will also be saving money by getting the most out of your fertiliser.

Overall, there are many benefits to using wicking beds while gardening. However, it is not a decision you should take lightly. It’s important to look at the disadvantages of wicking beds while deciding whether or not they are worth it for you.

Are Wicking Beds Worth It?

One of the biggest factors to consider when investing in wicking beds is the large cost involved; it is more expensive than other options such as regular raised beds.

Each part of a wicking bed must be constructed with sturdy and appropriate material so that it functions correctly; meaning that the cost of making a wicking bed can build rapidly. For example, this article estimates the cost to be as high as $50 per square metre. It is certainly not an easy and inexpensive hobby.

Additionally, although wicking beds don’t need watered very often they require other maintenance such as cleaning the drainage pipe and topping up the water reservoir.

If you’re not fully sure about a wicking bed, you may be better off choosing a less expensive option such as standard raised beds, that requires less maintenance.

Other Disadvantages to Wicking Beds

Besides the cost and maintenance involved, there are other disadvantages to wicking beds that you should consider before committing to a project.

They Often Start to Smell

It is very easy for fertiliser to build up in the reservoir of your wicking bed, and this can eventually ferment to form foul-smelling gases such as methane. If this does happen, there really isn’t much you can do beyond waiting for the problem to rectify itself.

There’s Little Room for Error

As mentioned, wicking beds can only successfully grow plants if very specific criteria are met. If not, you risk over-saturating the soil or causing leaks in the reservoir, meaning a waste of money and materials.

Additionally, wicking beds are not ideal for beginners due to the often unforgiving maintenance process. This won’t be a problem for the more seasoned gardeners among us but those with less experience might find it difficult to adjust to the maintenance process.

They’re Not Indestructible

Wicking beds are prone to damage by anything from harsh weather conditions to human error. When they break, it is an intricate, lengthy process to empty the soil and reservoir to fix it. You must consider beforehand whether this is something you will be willing to do.

One of the most common ways that gardeners break their wicking beds is by being too rough when planting. For example, many use trellises when growing tomatoes and blueberries to make sure the plants can support their own weight. If you’re not careful, you risk jamming the stick straight through into the reservoir.

Certain Plants Won’t Grow Very Well

Root vegetables thrive in wicking beds because they prefer damp soil. It stands to reason, therefore, that plants that prefer drier soil won’t take to wicking beds very well.

Additionally, the vast majority of plants grow best in soil that cycles between wet and dry, whereas wicking beds consistently have wet soil year-round.

Crops that grow best in dry soil include tomatoes, okra, peas and beans. If you wish to grow these, consider a different method.

The Dos and Don’ts of Wicking Beds

Here are some general tips when it comes to wicking beds.

DO Do Your Research

Whether you’re familiar with the concept of wicking beds or not, it can never hurt to expand your knowledge. There are many personal blogs available where gardeners indulge their experience of wicking beds – such as this one.

DO Rotate Your Crops Annually

The design of a wicking bed means that plant-specific diseases can remain in the soil for long periods. You should aim to crow annual crops and rotate them each year in order to reduce the risk of disease.

DON’T Use Plain Garden Soil

Normally, garden soil will not have the nutrients required to help your crops grow. If you can, invest in organic soil,  as well as compost or cow manure.

DO Get Creative

Did you know that you can make a wicking bed from a bathtub? Provided that the materials you use are sturdy and durable, you can make a wicking bed out of whatever you can think of.

DON’T Top Water

There are few specific circumstances in which you should top water your wicking beds. The vast majority of the time it will be sufficient to have them take in water from the reservoir.

DO Use Seedlings (Not Seeds)

Seedlings are tiny plants that have been grown from seeds, and they will quickly become accustomed to a wicking bed. On the other hand, seeds will often not have enough moisture at the top of the soil to germinate.

It’s advised that you grow your seedlings outside of the wicking bed, then transfer them into it once they’re ready.

Tips for Getting the Most Out of Your Wicking Beds

If you decide that wicking beds are right for you, you should take a few precautions to make sure they last.

What Materials Should You Use in Your Reservoir?

There needs to be a layer of something between the waterproof base of your reservoir and the soil. It should prevent the soil from getting waterlogged, but still allow enough water to pass through. Many recommend course grade scoria, for a number of reasons:

  • It’s porous and lightweight which allows water to reach the soil easily.
  • Despite being lightweight, it’s a very strong material – it can therefore hold up large volumes of soil.
  • The pieces are relatively large, which leaves plenty of space between the rocks to store water.

If you can’t get your hands on some course grade scoria there are a number of alternative materials you could use, including the following:

  • Gravel
  • Broken up pieces of brick
  • Old worn rope

Here is a great resource that provides tips on making your wicking bed’s reservoir.

Make Sure Your Space is Level

This is a tip that will apply to most gardening methods. Whether indoors or outdoors, the surface that your wicking beds are on must be level. If not, they will move around and cause the soil and reservoir to shift out of place.

It might be necessary to level the ground before setting up your wicking beds. If so, a shovel or rake can usually flatten standard soil.

Clean the Drainage Pipe Regularly

The drainage pipe on a wicking bed should be flushed out at least once every few months, to prevent it from becoming clogged.

Don’t Overdo It with Fertiliser

The fundamental thing about wicking beds is that, when something is put into the reservoir, it won’t come out. It can be tempting to add lots of fertiliser to your soil in the hopes that it will make your plants grow faster, but this can do more help than harm.

Crops will not grow in overly salty soil, which is often the result of too much fertiliser. Here’s a good resource to help you understand how much fertiliser is ideal for your wicking bed.

Cover the Drainage Pipe When Not in Use

When you’re not adding fertiliser or water to your wicking bed, the drainage pipe should be covered with a rock or something similar. This will stop critters from entering the bed and breeding within the reservoir, as well as preventing the entry of other general debris.

Conclusion

While wicking beds started off as an innovative way to prevent famine in arid climates, they are now used in homes and gardens across the world. Do you think wicking beds will work for you? If so, we wish you luck on your journey.

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