Anleolife Garden View: How to Better Drainage for Your Metal Raised Beds(II)

Anleolife Garden View: How to Better Drainage for Your Metal Raised Beds(II)

We have discussed in the last post about how to improve drainage for your raised garden bed in a total beginner’s respect. On the other hand if your raised bed is already built (or you now have the right location, height, and liner), it is high time to take the some other measures to improving drainage.

These steps may be inclusive of:

Add Soil Amendments

One of the most fun parts of gardening is playing with different soil amendments to make your plants grow better.

Some plants, like carrots, like smooth and sandy soil. Others, like blueberries, prefer acidic soil.

Remember to make your raised garden bed deep enough to hold additional soil amendments.

You have some options when choosing soil amendments to improve drainage in your metal raised garden bed. Here are a few options to consider.

First, you really should consider compost. This is the granddaddy of all soil amendments.

Compost is made from decomposed organic material, such as grass clippings, fallen leaves, dead plants, and kitchen scraps such as banana peels.  It is easy to make your own compost.

You can even add manure to your compost pile! Just make sure that it is completely decomposed before you add it to your garden. If it is not decomposed, then the salts or nitrogen in the manure can harm young plants.

If you are considering growing carrots or other plants that prefer smooth soil, then sand might be just the thing for you.  Sand makes the soil smoother, and allows for much better drainage.

Just be careful to avoid sand that has salt in it – otherwise, you will kill your plants before they even get started!

Finally, you can consider perlite or vermiculite, which are two soil amendments that improve soil drainage.

  • Vermiculite holds more water, and so it is best for seedlings and plants that need more water.
  • Perlite holds less water and allows more aeration, so it can be used for plants with low water needs.

Loosen & Aerate the Soil in Your Raised Bed

When soil is compacted, water cannot flow easily through the soil.  When you dig and move the soil around, you prevent compaction and aerate the soil at the same time.

When you aerate your soil, you create more space between particles, so that the water can move through faster.

Once your raised bed is built, using a rototiller to loosen the soil is out of the question (unless you use a very small and thin one!)  You will have to loosen your soil the old-fashioned way – with muscle power! Use a shovel or pitchfork to turn your soil over to loosen and aerate it.

Get Worms for Your Raised Bed

As an alternative to digging, you can use worms to improve your soil structure and drainage! Worms break down organic matter into soil, and they loosen and aerate the soil, allowing for better drainage.

You can buy worms online, at a bait shop, or at a garden center. You can also transplant them from other areas of your yard, or from a neighbor’s yard.

For excessively wet soil, incorporating a sandier mix can work wonders. Conversely, if your soil is clay-like or too light, adding compost enhances drainage and nutrient retention.

Good soil additions can include Compost, Coco coir, Worm castings, Grass clippings, Greensand, Perlite.

Things You May Want to Avoid in Your Raised Bed

If you want to improve drainage a little more, then there are a couple of things to avoid in your raised bed.

First of all, avoid a liner that does not allow proper drainage (for instance, a prefabricated or makeshift plastic liner that does not allow water through).  This may prevent wood from rotting, but it will prevent proper drainage, which will eventually kill your plants!

Also, avoid mulch & other ground coverings that will retain moisture in the soil and prevent evaporation by sunlight & heat.


Now, you have some ideas about how you can improve the drainage in your raised beds. You also know about some of the things to avoid so that you can prevent poor drainage in your raised beds.

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