A Guide to Improving Drainage in Your Raised Garden Beds

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Raised garden beds are becoming increasingly popular among gardeners. However, even though this sort of garden arrangement is known for better water retention, poor drainage can still occur. So, if you face drainage-related issues in your garden, you might be curious to know how to improve drainage in raised beds. This article will help you get rid of all your curiosities.

For improving drainage in your raised garden beds, you need to increase the height of the beds. You can build drainage channels, rain barrels, a pond, or a water fountain in the garden to enhance drainage. Using rocks, mulches, and soil amendments are also necessary in this regard.

Some other tips will also help you in improving drainage in your raised garden beds. A flawed drainage system can ruin all the hard work you give to your garden. Thus, improving it is a must. In this article, I will discuss a few essential tips for improving drainage in your raised garden beds, along with some other information related to the problem.

What Causes Poor Soil Drainage?

The type of soil plays a huge role in determining whether it will be well-drained or not. Thus, the main reason for poor soil drainage can be the soil itself. Besides, excessive use of water and fertilizers might also cause poor soil drainage.

Let’s discuss a few causes of poor soil drainage:

  • Type and Texture of Soil

There are different types of soils, such as clay soil, sandy soil, and loamy soil. Soil with lower pore space has less water retention capacity. Moreover, compacted soil is also a reason for poor drainage of your yard.

Clay soil cannot absorb water well as it has small particles and very little pore space. So, if your garden has clay soil, there is a high chance of poor soil drainage.

  • Excessive raining or flooding

The weather also affects your soil drainage capacity. For example, you might have to experience poor soil drainage due to frequent rainfall in your area. If you are living in a place where heavy rain often occurs, floods can happen too. Therefore, floods can cause poor soil drainage.

If the weather stays extreme, the soil cannot work on draining the heavy water flows continuously. So, excessive rainfall and frequent floods are two of the main reasons for poor soil drainage.

  • Using Too Much Fertilizer

Using too much of anything is wrong. Even though fertilizers are great for keeping your plants healthy, overusing them might cause problems. Too much use of different chemical fertilizers may cause depletion of necessary soil nutrients and a high level of toxicity.

For example, ammonium-based nitrogen fertilizers over time may cause soils to lessen pH levels and become acidic. So, plants won’t be able to take up all the nitrogen fertilizers. In addition, excess salts in the soil are often introduced by over-fertilization, reducing the ability of crops to absorb water.

  • Uneven surface level and faulty drainage system

Now, if your garden has a flawed drainage system or an uneven surface level, your soil will become poorly drained. Also, if your garden is in a lower area or has uneven ground, water will be accumulated in the area and stuck there if there is no way for it to pass away.

So, due to the lack of a sound drainage system, your yard may get waterlogged.

  • Over-watering the garden

Watering your garden is necessary. However, too little or too much water both are equally dangerous for your plants. Over-watering is harmful to your plants and the texture of the soil.

If you start over-watering your garden, the plants won’t use the excess water, nor will the soil absorb it. Thus, it will lead to poor soil drainage.  

11 Tips for Improving Drainage in Your Raised Garden Beds

Drainage is one of the essential factors to determine the well-being of your plants. No matter how hard you try, you won’t reach your garden goals if your garden has poor drainage. Of course, raised garden beds already have better drainage than regular gardens. Still, enhancing drainage will make it even more perfect.

There are several ways you can improve drainage in your raised garden beds. The following are few essential tips for improving drainage in your raised garden beds-  

1. Increase the Height of Beds

The first step for improving drainage in your raised garden beds is increasing the height of the beds. The lower the bed, the more drainage problems will occur. To make a higher bed, you have several quick and simple options. I would recommend the following.

You can make a higher bed by simply adding more soil and surrounding the bed with wooden fences or cement pillars. Be sure to even the soil level out so that water does not get stuck in the raised beds. No one wants watery beds, right 🙂

2. Build Drainage Channels and Rain Garden

To remove excess water from your garden, you must build underground drainage channels or drainage holes in your raised beds. These will reduce the amount of water accumulation in your garden and also reduce water waste.

Though it is better to build drainage channels before starting to make your garden, you can also make the channels after creating the garden as you can simply move raised beds from one place to another.

On the other hand, if you make a rain garden next to your raised garden bed, it will be beneficial to store rainwater and facilitate drainage of the raised beds. So, building a rain garden is an excellent option if you live in a low area and face frequent rainstorms. It will not only increase the beauty of your yard but also help you solve your drainage issues.

3. Loosen and aerate the soil

Water cannot flow freely through compacted and tightly packed soil. Therefore, aeration is essential for compacted soil. If you aerate the soil and make more space between the particles that will allow the water to flow easily. Moreover, the process will help open up a mass of soil to allow more oxygen and nutrients to reach deeper levels.

To aerate and loosen the soil, you can use your bare hands to till it. Or, you can use a shovel or pitchfork to dig it up. You can also use an aerator to do the job. However, consider avoiding tilling the soil when it is too dry or too wet.

4. Mix up different soils

Not every type of soil is well-drained. So, mixing up different soil can be highly beneficial to improve drainage. The most important advantage of this type of garden is that you can mix up different soil types and make the bed exactly how you want it to be.

Loam soil is the most ideal for good drainage. So, if your garden has clay soil, don’t worry. You can buy different types of soil from your nearby garden shop or nursery. Besides, adding sandy soil to your garden might also help with drainage. Thus, mixing up various soil types will help you have better drainage and help in your plant’s growth.    

5. Use rocks and stones

Adding rocks and stones to the bottom of the bed will help with drainage. If you put rocks in the bottom of your raised garden bed, you will provide more drainage space underneath the soil. In addition, a layer of rock in the bottom will help excess water to drain, holding it away from the plant roots.

You can use pebbles, crushed granite, or bluestone for improving drainage in the raised beds. Make a thin layer of 2-3 inches with the rocks within the specified frame before adding soil. You can do it using your hand or with the help of a rake.

6. Add compost and soil amendments

Soil amendments help to change the soil’s texture. There are many types of soil amendments. Composts such as grass clippings, fallen leaves, dead plants, and kitchen scraps like banana peels are also soil amendments.

In hard clay soils, soil amendments can raise nutrients and increase drainage. Vermiculite and perlite are two worth noting soil additives that can help with drainage. Vermiculite helps hold more water, whereas perlite helps with providing better aeration. Thus, both of the amendments can help you improve drainage in your garden.

7. Use mulch

Mulch is an excellent way to keep weeds at bay in your garden beds while also improving drainage.

Mulch not only helps to keep moisture in the bed, but it also helps to spread it uniformly. Try applying mulch to your raised beds if you’re having trouble with water pooling or draining too quickly out of those corners. Moreover, mulches will provide structure and support to the underlying soil as it decomposes.

8. Add water features

Adding a water feature to your garden will not only improve your garden’s beauty but also increase drainage. Fountains, rain barrels, and ponds are some of the most common water features people install in their gardens. Each of these water features does an excellent job of supplying moisture to the soil around the garden’s plants.

A pond will help gather the excess water from the ground, which is highly necessary for good drainage in raised garden beds.

9. Grow specific plants

Some plants can help to improve poor drainage in your garden bed. Using some specific plants, you can make a focal point to help have good drainage in the garden.

Choose water-loving plants, such as marsh marigolds, cardinal flowers, and turtlehead. As these plants require more water for doing their biological activities, they will absorb excess water, and thus, will play a significant role in solving your drainage issues.

10. Use cover crops and sheet composting

Many people have a misconception that the cover crops are only for weed control. Well, weed controlling is one of the benefits of cover crops for sure, but this is not the only benefit.

Cover crop’s taproots help in soil aeration. While only some cover crops pull up nutrients for other surrounding plants with their deep roots, basically all of them help to loosen up soil. As compacted soil is one of the top reasons for poor drainage, using cover crops will be helpful in this regard. However, it would be best to plant the cover crops in the fall or spring to get the desired results.

Sheet composting can also be used to solve your drainage trouble in the garden. To begin, wet the cardboard or newspaper and place them over your garden soil. Then incorporate green and brown materials such as sawdust, compost, wood chips, peat moss or animal bedding.

Layer your garden in the same way you would a compost pile. It would be best if the layer is 3-5 inches thick.

11. Attract worms

You can use worms instead of digging to improve the structure and drainage of your soil! Worms decompose organic matter in the ground, loosening and aerating the soil to improve drainage. And, as I have mentioned earlier, loose soil and aeration are vital for good drainage.

Worm-heavy soil drains ten times faster than worm free soil, and water infiltration is six times higher. So, if you want to attract more worms to your raised beds, you have to ensure more bacterial production and add more and more organic materials.

You can also buy worms online or from your local gardening shop. However, keep in mind that not all worms are beneficial. For example, Lumbricus Terrestris, Lumbricus Rebellious, Eisenia Fetida are a few advantageous worms for your garden. So, make sure you have only the helpful worms in your garden.

Why Is Good Drainage Necessary for Your Raised Garden?

Good drainage is necessary for your raised garden to keep your plants healthy and fresh. In addition, it helps to stop water accumulation in your garden.

Like any other type of garden, good drainage is also necessary for your raised garden. Here are a few importance of good drainage in your raised garden-

Ensures proper growth of plants

For plants to grow properly, a garden must have good drainage. When water may drain to the bottom of the soil, it prevents water from sitting near the roots, which can cause the plant to grow improperly or not at all. Root rot occurs when a plant’s roots rot due to sitting in too much standing water due to poor drainage.

Not only will the root start to rot, but your plant will also begin to get affected by various diseases. Poor drainage causes beneficial worms and bacteria to die. Moreover, poorly drained soil lacks the necessary nutrition that helps in plant growth.

A plant can eventually die and succumb to root rot if it does not have adequate drainage. Therefore, proper drainage is the most effective way to avoid root rot. If you want your plants to be healthy and fresh, there is no alternative to making sure your garden has good drainage.

Reduces soil erosion

Keeping soil well moist is critical to making a good garden. If your garden does not have a proper drainage system, the soil will stay wet most of the time, which will cause excess soil moisture. Stagnant water can cause soil to become muddy over time, causing erosion. Drainage helps to prevent soil erosion by reducing nutrient loss from runoff.

If water stays locked in your garden, more soil will be washed away from your garden. So, no matter what amendments you mix on your ground or how you prepare the soil won’t matter as everything will go away with the water. Thus, you must have a sound drainage system in your garden to reduce soil erosion.

Prevents waterlogging

Drainage systems steer water away from your garden, preventing water accumulation that could contribute to flooding. Overflowing water in your yard will destroy your plants. In addition, drainage systems often prevent stagnant water from forming, promoting harmful plants and mosquito breeding.

If there is water all over your garden, you also won’t get to do gardening properly as water will narrow your pathways. However, if there is good drainage in your garden, no matter how much it rains, water will find its way to go away.

From the above discussion, it is clear that good drainage has lots of benefits. Thus, it is crucial to have raised beds with adequate drainage. It will not only prevent the plants from being over-watered or under-watered, but it will also reduce the risk of diseases linked to water issues.


Good drainage is the first step to give your garden the desired shape. If you can maintain your garden well, gardening will be a lot simpler and straightforward for you. By now, you’ve figured out how to improve drainage in raised beds. On top of that, you also got to know the importance of having good drainage in your garden.

So, make sure your garden has well-maintained drainage and enjoy a fantastic experience of gardening. Thanks for reading through. Hopefully, this article helped solve your trouble. Have a great day!