Last Updated on July 30, 2022 by Guillermina
Find out what experts say about putting rocks for drainage in pots.
It’s no secret that all plants will look much better if your pots are clean and have good drainage. Drainage is crucial for the health of every plant planted. Unfortunately, a gardener can face all sorts of problems and difficulties if the soil of the plant doesn’t drain properly, including diseases such as root rot.
There are proven ways to increase drainage in pots, and many of them are the subject of study in horticultural schools, and they are also used by numerous plant production nurseries. Therefore, in this article, we will explain the science behind putting rocks for drainage in pots.
Should You Use Rocks For Drainage In Pots?
For a long time, gardeners were adding a layer of rocks for drainage in pots. They did not do it voluntarily, but it was ordered by the profession at the time. However, as time goes on and the profession progresses, according to research conducted by the University of Illinois, placing rocks for drainage in pots is considered a false belief due to the presence of a saturated zone.
Disadvantages Of Using Rocks For Drainage
- Greatly limits the amount of soil that is put into the pot.
- Saturates the soil.
- Reduces aeration.
- It reduces water retention which in turn doesn’t meet the needs of the plant.
What Is A Saturation Zone?
We won’t procrastinate and bother you with a kind of boring explanation, so we’ll get to the point right away.
When you water your plants, the water moves down through the soil due to the force of gravity. The roots get the necessary moisture and the rest of the water drains out of the pot. If you use rocks for drainage in pots, water percolates through the soil but gets sideward through those rocks.
As a result, the saturated zone is raised closer to the roots which unfortunately cannot exchange gases with the outside due to prolonged staying in this wet zone. This can eventually lead to wilting of your plants.
When Would You Need Rocks For Drainage In Pots?
But don’t be fooled because there are still situations where the use of rocks is very acceptable. Wondering when? Keep reading and find out.
Too Big Drainage Holes
Placing holes larger than necessary at the bottom of the planter happens much more often than you would ever think. The consequences of this can be quite undesirable, i.e. the soil could run out of the pot with the water during each watering.
In addition, as a result, water runoff can sometimes turn yellow or brown, depending on the composition of the soil, and damage the places where the container is placed. You can even use a plant saucer, however, it will only prevent the floor from getting dirty, and will not solve your problem.
Placing rocks for drainage in pots will reduce the size of the drainage hole and prevent soil from leaching. Simply place the rocks flat on the bottom of the pot just to cover the holes.
Placing rocks on the base of a plant pot before filling the soil in this case is a pretty wise idea. Wondering why? Because it will provide a much-needed anchor that will help the plant stay upright during strong winds. In addition, it will work well for those tall pots with a small diameter or base.
What Are The Best Types Of Rocks To Use?
Truth be told you can use different types of rocks for drainage in pots. Read below which are our favorites.
Lava rocks are a great option because they are porous, absorb and slowly release excess water.
Limestone as it gives your plants many benefits because it contains many minerals besides calcium carbonate.
Slate-like rock is a sedimentary rock made of clay and volcanic ash which is one of the best options if you are considering putting rocks for drainage in pots.
Cinder Blocks are almost identical to pumice stones and are made from fragments of solidified lava; gardeners simply love to use them at the bottom of their planting pots.
We think that everyone will agree that finding the best drainage material for potted plants is a kind of combination of availability, cost, effectiveness, and perhaps most of all, ease of use. Many materials designed for this purpose can provide better drainage in pots, and when used properly can bring many benefits to your favorite planted plants.
Until recently, gardeners used only rocks for drainage in pots, but today this is not the case. With the progress of the profession come new insights that change the knowledge and practices in gardening as well as in all other spheres of human activity.
Do you use rocks for drainage in pots or have you found some new methods? Let us know below.
What Stones Are Best For Drainage In Pots?
Lava rocks, limestone, slate-like rock, and cinder blocks are the best types of rocks to choose from if you plan to place them at the bottom of your planting containers.
Is It OK To Put Rocks Around Potted Plants?
Until a few years ago, you weren’t even allowed to plant a plant without placing rocks on the bottom of the planting pot. Today, things are a little different, and their only purpose is no longer exclusively drainage. Rocks are mostly used to add a touch of aesthetics to the plant, prevent water loss, fungus gnats, weeds, splashing, and many other things.
Accordingly, it’s perfectly fine to use them, but you don’t have to if you feel you don’t need them.
How Deep Should Rocks Be For Drainage?
It is enough to place only one layer of flat rocks on the bottom of the planting container.
What Can I Use For Drainage In Pots?
Here are the best options if you want to add drainage to your pot:
- Activated Charcoal
- Potting Mix