Why You Should Put Grit on Top of Plant Pots?

You might be wondering whether you should cover your houseplants with grit. You may have seen it commonly done in nurseries with indoor plants. But why do they do that? Is it purely decorative or do they offer other benefits?

You should add potting grit to plant pots to increase their aesthetic value. It helps the plant flourish by increasing its water retention and drainage capacity. Also, it protects the plant by preventing overexposure to sunlight and eliminating the conditions needed for growing fungus gnats and weeds.

This article will give more reasons why you should consider adding grit to potted plants!

Reasons to Add Grit to Plant Pot

1. Aesthetics

Often, potting grit is used to enhance the plant’s look, giving it a classy look and allowing it to blend in with any modern décor. Potting grit is mainly used as decorative coverings for cactus plants.

While there are potting grits of many colors that can be used to increase the aesthetic value of the plants, white is most frequently used as it best contrasts with the plant’s green color.

However, the kind of rocks used in the potting grit should be a consideration. Some potting grits have rocks containing the ability to leach limestone. This disturbs the soil’s pH level, damaging the plant and rendering it unable to absorb any essential nutrients.

You can make your own gritty mix at home by following the instructions in this video below:

2. Water Retention

When you add potting grit to your plant pot, you essentially shade the soil below it and also reduce its temperature. Because of this, less water evaporates from the soil leading to better water retention. The top layer of potting grit also covers the soil, preventing dry winds from taking water out of the soil.

One study even revealed that some grits increase the soil’s nutrients and plant height.

3. Drainage Capacity

Grit can be added on top of plant soil to improve the plant’s drainage capacity. The types of rocks in the potting grit include perlite, stones, and vermiculite. These rocks create air pockets along with adding texture to the soil. As a result, the soil stays airy, loose, and well-drained.

Suppose you remember that compared to the rest of the soil, you must know that the stones and sand in potting grit are significantly heavier and larger. Therefore, this will help to reduce the weight of clay and other elements of the soil that obstruct drainage.

It’s also important to remember to use a pot with a drainage hole at the bottom. Pots with no drainage holes at the bottom are not made for use with living plants but decorative plants instead. Adding potting grit at the bottom of the plant also does not help drainage but worsens it by bringing the water table to the roots and promoting plant rot.

4. Overexposure to Sunlight

Since potting grit serves as a cover for the soil, it protects from overexposure to sunlight. Using potting grit containing gleaming, polished rocks are recommended to protect the soil and roots from sunlight. These rocks not only cool down the soil but also reflect back a large portion of the direct sunlight that the plant is exposed to.

5. Fungus Gnats

These are tiny insects that look similar to mosquitoes. Even though they have a short lifespan, they also carry fungi such as phytophthora and pythium, damaging plants. Fungus gnats thrive in damp soil conditions, mainly if there is rotting vegetation and fungi.

The top 14 inches of the soil is where fungus gnats typically deposit their eggs. Laying potting grit on that area blocks the fungus gnats’ access to it. This is essential if you want to get rid of these pests.

A quarter inch of potting grit can be added to prevent draining out water quickly so that the ideal conditions for the growth of fungus gnats are not replicated.

6. Weed Growth

Just as with fungus gnats, adding potting grit to plant pots prevents the ideal conditions needed for weed growth.

7. Pets

Anybody living with pets understands their curious nature. Pets love to play with soil and potentially create a mess by tipping the plant over.

Covering the topsoil with grit, you’re covering the potential temptation for pets to start digging.

8. Soil Splashback

Going back and cleaning up after you water the plants each time can be bothersome.

Potting grit will serve as a barrier between the water and soil, breaking the force of irrigation and preventing soil from splashing back on the pot’s interior or the flooring.

Not only does it prevent splashback, but it also prevents water from evaporating into the air, which may lead to the plant requiring less watering.

Frequently Asked Questions

Should Gravel be Added to the Bottom of Pots?

The misconception is that adding rocks or gravel to the bottom of a plant container would increase drainage. That is untrue. Plant containers shouldn’t have rocks in the bottom. When you fill plant pots with drainage holes with gravel or rocks, the drainage is not improved; rather, the water saturation zone, which causes root rot, is increased.

How to Choose Garden Grit?

Crushed rocks like limestone or granite create sharp sand and horticultural grit. Check out what kind of stone is used in the grit or sand to determine how acidic or alkaline it is. Different varieties of rocks have different pH levels.

How Often Should Houseplants be Repotted?

The ideal time to repot your plants is typical during the growing season, which runs from early spring to late summer.


Concerned plant parents often wonder whether adding grit to their plants is a good idea. Potting great can be beneficial for plants in many different ways. In this article, we discussed the various benefits of adding potting grit to plant pots.


Hi I'm Mike, a self-proclaimed plantician (an invented profession to describe a plant enthusiast). Based in Sydney Australia, I enjoy the great outdoors and the greenery things around the garden, in particular, indoor climbing plants.

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