If your garden soil isn’t draining properly, it will prevent your plants from growing and could even lead to soil compaction. Altering the dynamics of your soil will create a more suitable environment for supporting biological systems and plant growth over the long term.
To make your garden soil drain better, you can use a mixture of organic and inorganic materials, such as compost, worm castings, and fertilizer, apply garden sand to very heavy soils, and occasionally till the topsoil. Raised garden beds are great for drainage, and you can even build a rain garden.
This article will discuss the best ways to make your garden soil drain more efficiently. I’ll discuss the advantages and disadvantages of each option and give you some valuable tips on how to alter the drainage without damaging the biological structures of the soil.
1. Apply Organic Materials to the Soil
One of the best ways to improve drainage in almost any kind of soil is to distribute organic materials through the first few layers of topsoil. Organic matter contains microbes and other organisms, and their activities help create better structures for drainage and aeration in the soil.
There are a number of organic materials that you can use to improve the drainage of your soil, and many of the options are easy to source. By far, the best organic materials for soil that drain well are compost and worm castings.
We’ll explore these and a few other options below to help you improve the drainage of your garden soil.
Compost is the ultimate winner when it comes to addressing soil concerns. It’s easy to make yourself at home and hardly costs a thing. It’s suitable for practically any type of soil and can be altered depending on your soil’s needs.
If your soil is quite heavy and clay-based, you’ll find that adding compost to the first few inches will separate the particles and promote microbial growth within the soil, improving aeration.
The soil needs enough oxygen for these processes to occur, and the organic matter in compost pushes open the soil pores to create space for water to drain away effectively.
Compost ultimately changes the environment to promote the growth of organisms that can offer sufficient nutrients to your plants. Being a product of decomposition, the decayed materials in the mixture supply nutrients and improve soil texture over a long period.
The reason why compost is considered so good for soil drainage is that it contains something called humus. This is an organic form of fertilizer that helps the soil manage its water content so that it can absorb the amount that it needs while efficiently draining the rest.
Adding compost to your garden soil will mean that you won’t need to water your garden quite as much. And when you do, you won’t find any stagnant water that might drown the roots of your plant.
Compost can be made from scratch without any fancy materials. All you need is food scraps and a few other things to make the perfect fertilizer for your garden.
Kitchen Waste That Can Be Composted
If you’re set on using compost to help your garden soil drain better, you can use almost anything from your kitchen. However, it’s best to steer clear of dairy and meat products unless you’ve got a good system to prevent flies and pests.
Using these products in your composting means that you’ll find your compost pile smelling very bad once they start to decay, which will attract pests to your compost bin. Meat products like bone also take a long time to break down, which is not ideal for regular hot composting at home.
Instead, you can use the scraps from any fruit or vegetable you use in the kitchen to make compost. This includes vegetable shavings, fruit seeds, and even onion skins will help the process nicely. You can also use eggs—but only the shells, since throwing expired eggs into the mix is not generally advised.
To make a useful compost pile, you’ll need a mixture of nitrogen-providing and carbon-providing ingredients. The nitrogen will come from things like grass clippings and vegetable scraps, and the carbon will come from things like newspaper and twigs from the garden.
One thing to bear in mind when making a compost pile is to avoid using ingredients that might transfer diseases to your soil. This includes things like cat litter or anything that contains chemicals, like grass clippings that have been recently sprayed with pesticides.
Worm castings are the cast-offs of earthworms. The worms burrow into the soil and consume organic materials that are then secreted back into the ground, creating organic castings that feed into the biological soil system.
Worm castings can help you improve your soil’s drainage capacity by pushing open dense soil pores and creating space for aeration and water waste. Worm castings are also full of nitrogen, which is one of the most essential components of plant growth.
Mix your castings directly into the soil and water the area deeply to allow the soil to take full advantage of the new nutrients. A one-time application of worm castings will improve the soil for many months. The castings create a cyclical biological process that means the soil can continue using its nutrients over a long time.
You can find worm castings in your local nursery or online from several brands. However, it’s worth bearing in mind that most commercial worm castings mixtures that claim to be 100% pure actually contain synthetic materials. Be sure to get worm castings that consist of 100% organic material with no additives.
If you’re an avid gardener, you know all about the benefits of manure to enhance soil structure.
Manure acts in a similar way to compost and adds organic materials that create better drainage systems over the long term. It changes the spacing of soil particles to ensure a good flow of oxygen and nutrients throughout the soil.
The organic material helps retain necessary water and nutrients and drains away the excess, ensuring a healthy garden.
With manure, a little bit goes a long way. It can offer plants a slow-release fertilizer that benefits the soil. It’s also super easy to use. All you have to do is mix it into the top few inches of soil and let the magic begin.
One thing to be aware of when using manure is that some types of manure won’t be as effective as others. For example, horse manure isn’t usually advised since it often contains weed seeds that the horse hasn’t been able to digest.
So, if you’re unable to filter these seeds, it leaves you with a pretty big problem as you’ll have weeds sprouting up in your garden. For this reason, it’s best to use relatively well-filtered manure for the best results.
If you’re a gardener on a budget, leaf mulch is an excellent way to improve your garden soil’s drainage . You can collect leaves from your garden and shred them up to provide an equally distributed organic fertilizer that will help to sustain biological productivity in the soil.
Leaf mulch also has the added benefit of maintaining the overall temperature of your soil. This means keeping the ground warmer during cooler months and promoting better frost resistance. Placing the leaves in the top few inches of soil will allow them to break down slowly and create extra organic components that will encourage efficient drainage systems.
The best time to use leaf mulch for your soil’s drainage is just after summer. This will allow the leaves to fully break down before the spring months when you’ll most likely be planting.
In a similar way to leaf mulch, shredded bark is another recyclable garden material that can be used to improve soil drainage.
It also promotes moisture retention and aerates the soil by breaking up the soil particles. Being rich in cellulose, bark takes a long time to break down in the soil, preventing soil compaction.
Shredded bark, therefore, creates a better soil structure for organic compounds to break down through microbial growth. It also helps with water retention, just like any other organic matter.
Pine bark is often the most popular choice since it is also long-lasting and will help your soil stay clear of pests. Some gardeners are afraid that pine bark is slightly acidic and might acidify the soil. The long-lasting nature of pine bark means it decomposes slowly and typically doesn’t have any significant impact on soil pH. Still, pine bark should constitute only a small portion (up to 10%) of your garden soil mix.
Why You Shouldn’t Use Peat Moss to Improve Soil Texture
Peat moss was once considered one of the most popular soil additives for drainage, aeration, and soil acidity. However, we’ve become aware of several problems with peat moss over the years, so using it for soil drainage is not a good idea.
For starters, peat moss is only suitable for plants that love acidic environments. If the only thing you want to do is improve the structure of your soil to improve drainage, peat moss probably isn’t your best bet.
Additionally, peat moss harvesting is now considered terrible for the environment. Peat bogs are naturally occurring, dense carbon storage regions that, once depleted through harvesting, release carbon into the atmosphere. This is also a problem for the wildlife in those areas since the harvesting process effectively destroys their home.
So, if you want to promote drainage in your soil, use the organic materials we’ve discussed above in lieu of peat moss.
2. Use Coarse Garden Sand for Poorly-Draining Clay Soil
Coarse garden sand is an excellent way to promote drainage in poorly-draining soils. This includes super dense clay-based soils that contain structures that are typically difficult to alter.
Sand changes the structures to break down heavy soils with densely packed particles like clayey soil. This allows oxygen to enter the soil and gives it a better capacity to drain away moisture that isn’t needed.
Using sand is one of the quickest ways to promote good drainage in the soil. It’s faster than organic materials and will last a long time.
However, it’s good to bear in mind that very dense soils will need a lot of sand to make a difference. At the same time, using too much is detrimental to your soil and will cause needed moisture to leach out.
Avoid Using Play or Beach Sand in Your Garden
Coarse garden sand is often called builders sand and is typically used on construction sites. The kind of sand you use is actually very important since using the wrong type won’t help promote good soil drainage.
For example, it’s not a good idea to use beach sand in your garden soil. Beach sand contains sodium chloride that has been absorbed from the sea, so it won’t promote drainage and will instead destroy the roots of your plants. Additionally, play sand is not a good alternative since it contains particles that are too large for use in your garden.
3. Cover Crops Increase Drainage Over Time
Cover crops are often used by commercial farmers in colder months when growing edible plants isn’t feasible.
If you want to improve your soil in preparation for the spring and summer months, when planting becomes more viable, cover crops will help the soil retain its drainage and aeration levels over this period.
Cover crops often have very long, strong roots that can help the subsoil retain adequate drainage and promote the longevity of microbial activity within the soil. They keep the soil healthy in preparation for planting.
These crops can promote cyclical biological processes that retain soil structure over time. Organic materials are also boosted through the presence of worms and good bacteria.
You can use grasses, such as annual ryegrass, as an effective cover crop. Rapeseed is also an excellent option to plant as a cover crop.
4. Use a Garden Fork to Till Your Soil
Manually tilling your soil is a good way to open soil pores and improve drainage over time. Any dense structures within the soil can be broken up, and using an equal distribution of organic materials while tilling can help improve the soil’s aeration.
Bear in mind that tilling too much will disturb the natural microbial processes in the soil, so it’s good to use this option infrequently and very gently to avoid damaging the soil. Tilling once every few months is an excellent way to maintain open soil networks, allowing moisture to drain away without pooling on the surface.
The best way to till your soil to promote drainage is to use a wide-toothed fork since this helps to prevent damage to the soil while tilling.
How Much Tilling Is Too Much?
Tilling too much is never a good idea—but how much is too much?
Generally speaking, it’s considered too much to till your soil every week. Tilling every month, if you’ve got a high turnover of plant growth, is usually fine, but it’s a good idea to limit it as much as possible if you’ve got plants that take a long time to grow.
Tilling your garden just before planting seedlings is ideal since it helps to loosen the topsoil so that young roots can easily push down into the subsoil. It allows the soil to drain excess moisture efficiently and helps the plants grow big and strong.
Lastly, it’s good to remember that you should only till your soil when it’s dry since tilling in wet conditions promotes soil compaction.
5. Work a Soil Conditioner Into the Topsoil
Soil conditioners help the soil become a good base for plant growth. They alter structures to promote good aeration channels, drainage conditions, and bacterial growth, ultimately keeping the ground in good condition over the long term.
Using a soil conditioner alongside organic materials such as compost, earthworms, or leaf mulch will give your soil the boost it needs to open up its drainage capacities. These organic materials take the soil conditioner and burrow it into aeration channels, distributing it evenly throughout the soil.
Chemical fertilizers, perlite, and gypsum are the three most popular soil conditioners to promote better drainage.
Chemical fertilizers are the synthesized versions of organic fertilizers, such as compost. These are artificial substances that can alter the structures of the soil to promote good drainage channels.
While chemical fertilizers in large quantities can have a negative effect on the soil’s properties and the surrounding environment, small doses can be perfectly acceptable in maintaining a good soil structure.
In fact, using a lot of chemical fertilizer can result in nutrient leaching from the soil, removing beneficial bacteria from the earth that help support plant growth.
Perlite is a substance derived from volcanic areas and can be used to promote better drainage in soils. It is porous in nature, so it can help the soil retain water, but it is also helpful to maintain drainage at reasonable levels. You can mix it with organic materials for the best results.
It lasts for an incredibly long time, so it’s a worthwhile purchase if you want to make your garden soil drain better. Small handfuls of perlite are enough to completely alter the soil for the better.
Perlite is considered a soil conditioner because it improves the overall structure of the soil. It doesn’t have any bacterial ingredients, so it won’t help the nutrient density of the soil, but it will increase the amount of oxygen the soil can take in, allowing your plant roots to thrive. It comes in many different sizes and can increase the level of drainage in heavy soils.
If you’re looking for cheaper alternatives to using perlite, you could also check out my other article: 14 Best Substitutes for Perlite in Gardening
Gypsum is another soil conditioner that can help your soil drain better. It creates porous structures in the soil so that the soil is less likely to stick to itself, creating channels to drain away excess moisture. Also known as calcium sulfate, gypsum is popular among gardeners everywhere.
One thing you’ll need to bear in mind when using gypsum is that it will only be effective on soils that are considered sodic. This is when too much sodium is present in the soil, affecting the structure of the earth and preventing it from draining properly. If your soil is sodic (which you can figure out through a basic soil test), then gypsum is the right choice for you.
6. Create Raised Beds for Greater Drainage Control
If you want your garden soil to drain well, use raised beds since they give you a greater level of control over the soil and therefore make it much easier to alter should the need arise.
Raised garden beds are sometimes considered better for growing vegetables and fruits since the soil is usually layered, and you can use many different materials to create better drainage and aeration systems.
There is also a much lower potential for mistakes in a raised garden bed since you’re making the area from scratch. Raised beds also have a lower chance of compacting over time—provided you’re looking after the area properly.
Choosing the Right Design for Your Garden
One of the best things about raised garden beds is that they are inexpensive to build and last a long time. Once you’ve built it, you can reuse it every year. They come in a variety of designs and can be made of just about any material. This means that they’re one of the easiest ways to elevate the aesthetics of your garden.
If you’re not interested in making one yourself, you can always purchase a ready-made raised garden bed to save you the hassle. Be sure to get a high-quality raised garden bed, as the cheap ones will break quickly.
If you did want to take the DIY route, there are several types of raised beds, and it’s essential to choose the one that’s right for you before starting:
Lifted Soil Mounds
Lifted soil mounds aren’t built with a wood or metal structure and are just mounds of soil pushed upwards from the ground. They allow you to use your normal garden soil with the added benefit of greater control over drainage, aeration, and organic matter.
Wooden raised beds are typically the most popular type of raised bed and look good in any garden setting. They are made from either treated wood or basic wooden planks and can be built as long or as high as you want. However, the best width for this type of raised bed is around 4 feet (1.2 meters).
Metal raised beds are made from alloyed metals and are often considered the most stable type of garden bed. They can be bought ready-made, or you can build them from scratch yourself.
Natural Log-Based Beds
Natural log-based beds don’t necessarily have a side structure but are built on top of wooden logs. The logs, as they decay, become natural providers of good bacteria and will help your raised bed drain well over time.
Soil Layering for Good Drainage
To have a successful raised bed with good drainage capacities and support plant life, you’ll need to layer the base well with lots of ingredients to keep the soil balance healthy. Think of your raised bed like a lasagna—the more layers, the better it is.
Each layer should have a different ingredient. A good example would be pre-packaged soil on the base over a few logs, then a layer of compost, then perlite, then more soil, and so on.
The top layer of your raised garden bed should be commercial topsoil, and you can rake in a few organic materials to boost its potential to support plant growth.
This layering technique ensures that your plant roots have plenty of nutrition right through the bed, from top to bottom. It’s easier to control how well your soil is draining using the layering method, and you can change the soil if you want to alter the structure.
Another bonus of raised beds is that they are often much more accessible than standard garden soil. They look much neater, and you can organize your plants however you like.
Organic materials are probably the most crucial part of raised beds. A really good compost will enable your raised beds to create their own cyclical nutrition processes that will keep your soil thriving over the long term.
7. Ensure Your Soil Isn’t Compacted
Overly compacted soil is one of the most significant indicators of poorly-draining soil. Soil structures need to be somewhere between loose and compact in order to carry plant life and allow organic processes to take place in the pores.
Non-compacted soil has the capacity to promote life through aeration channels, adequate moisture retention, and sufficient filtration. If your soil is too compact, these processes become almost impossible.
If your soil is too compressed, you may find that your plants won’t grow—and they could even die if the ground is very hard. Getting to the root of this problem means promoting a better soil structure for your plants, and that means improving the drainage first to stop your roots from suffocating under the soil.
Dangers of Overly Compacted Soil
If your soil is too compact, moisture won’t be able to trickle down into the subsoil. You may find water pooling on the topsoil after you water it, and your plants will start to weaken over time.
Since overly-compacted soil doesn’t have the capacity to sustain healthy bacteria and biological processes that help plants thrive, it may become very difficult for anything you’ve planted to survive for very long.
Even hardy plants like shrubs that have been in the garden for a long time can suffer ill effects from compacted soil.
How to Loosen Compressed Soil for Good Drainage
To loosen the soil, you need to consider the essential variables in soil structure. Your soil needs to have access to oxygen, so it needs to be fluffy (and the topsoil should be bouncy), and it needs to have adequate space to filter moisture down into the subsoil.
Watering slowly is the most important factor at this point. If you flood the area too quickly, water will simply pool at the surface. Watering slowly and deeply to allow the moisture to trickle down will help you to fix the problem.
Have a look at the steps below to loosen your garden soil and promote better drainage:
1. Turn Over the Compacted Soil
Use a wide-toothed garden fork to pull open the compacted soil and turn it over. Try to be as gentle as possible and only turn over the first few inches of soil.
2. Add Organic Matter
Sprinkle a few handfuls of organic matter, such as compost or worm castings. You can now turn the soil with the rake once more.
3. Water the Area Deeply and Slowly
After watering deeply and slowly, leave it for a few days to take in the new organic matter, and then repeat steps 1 and 2 one more time.
4. Leave the Area for Another Couple of Days
After a few days, add a handful of perlite. Distribute the perlite evenly across the surface. Turn the soil again (gently) with the garden fork and water it deeply.
After this, your soil should be in slightly better condition. Try to avoid walking over the area since this will re-compact the soil, and you’ll have to start all over again.
If the above steps don’t work, your soil is likely too compact for use and will need cover crops and a couple of months to recover. After planting your cover crops, leave the area to decompress naturally and use raised garden beds instead.
8. Design a Rain Garden to Collect Drained Water
Using a rain garden is a last resort since it can be an expensive endeavor. However, if you live in an area with a lot of rain throughout the year, you’ll find it will save your soil and prevent it from getting waterlogged, allowing it to drain much better.
Rain gardens are dug 3.3 feet (1 meter) or so into the ground and are designed to collect excess water that would otherwise sit on top of your garden soil. You can use PVC piping to create channels that dip into the rain garden and plant lots of water-loving plants in the area to soak up the excess water.
Rain gardens are a beautiful addition to any garden and will allow your soil to absorb the water it needs, draining away the excess moisture so that it doesn’t drown your plant roots. Shrubs and grasses that don’t mind intermittent downpours can be planted in the area, making your garden look like a landscaping dream.
This is essentially a clever way to make use of excess rainwater. The water collects through the channels and ends in a pond-like landscape full of lush native plants that happen to love moist environments.
The soil is dug downwards to create natural dips, pushing rainwater to the rain garden instead of pooling all over a level garden.
Additionally, excess water in a rain garden will sit for long enough so that much of the moisture can evaporate, leaving enough water for your water-loving native plants and keeping the rest of your garden free from drowning.
You can get super creative with your rain garden and design it however you like. You can place decorative items and landscaping rocks around the area. If your garden is on the larger side, you’ll love designing and building it.
For more detail, have a look at this YouTube video from Garden Fundamentals:
The Best Plants for a Rain Garden
To have an effective rain garden, you’ll need plants that can withstand a lot of moisture. A thick cover of plant life also ensures that the soil underneath the rain garden doesn’t erode over time.
Planting a good layer of shrubs is the best way to ensure that rainfall gets absorbed into tall, thick branches before hitting the soil, creating a much better system for drainage. Some rain garden plants require full sun as well as lots of moisture, so you’ll need to bear this in mind before deciding the location.
Cardinal flowers and marsh marigolds are good options for a rain garden and can grow very tall. They look beautiful as well!
Additionally, purple coneflowers are a good option for those who love thick flower coverage that mimics wildflowers. They are very tall and love the sun and moisture-rich soils, so they’re perfect for a rain garden.
To make garden soil drain better, you should use a mixture of organic materials such as compost and worm castings, coarse garden sand, and soil conditioners. Cover crops also provide an excellent way to improve drainage over time if you’re not using the soil, and remember to manually till the earth no more than once a month.
Keep your soil from becoming compact, or, in the worst cases of soil compaction, you can use raised garden beds to maintain greater control over the drainage capacity of your soil. Alternatively, build a rain garden for a beautifully landscaped drainage garden.