What is a horticultural grit? Also known as garden grip and sand, it can help you transform your outdoor space. You can use grit to support your soil or to sow seeds, but also for mixing with garden soil when potting alpine plants.
Simply put, horticultural grit is a gardener’s best friend in preventing compact and waterlogged soil. How to use it effectively? What is it?
Is there a difference between horticultural grit and horticultural sand? We try to answer all your questions.
Starting from the beginning, horticultural grit is composed of crushed rocks, mainly silica, limestone, quartzite, or a few others. These stones are extracted from the ground, then crushed, and then washed to remove other soil content. In the end, they are placed in sturdy bags for delivery where you get sharp-edged grains 1-6mm in size.
A fully versatile product, most people use it to improve drainage and aeration in the soil. Here are some benefits of using it:
- Provides extra drainage when added to compost
- It is the perfect accompaniment for succulents and alpines
- Aids drainage if mixed into heavy soil
What is it?
As we mentioned before, horticultural grit is basically washed grit with a particle size of 1-4mm or 2-6mm. It has a neutral pH and it is intended for use in some potting mixes you can make up yourself.
Any grit or gravel that has been washed sometimes might be called horticultural grit. And the main usage is to aid drainage.
We know drainage in heavy soil or clay-based soil can be a challenge. But you can improve drainage by adding horticultural potting grit. These tiny pieces of grit create air holes. It allows water to drain through the soil more effectively and efficiently. But that is not all. These new pockets also aid root growth as the root has room to expand.
What is it made of?
We mentioned before the main components of grit. But let’s go over each one separately. As we said before, the individual parts are much cheaper than the finished product. Yes, components can vary from one manufacturer to another. Yet, most of the products are made of a mixture of limestone, silica, or quartzite.
Limestone is a hard sedimentary rock composed of calcium carbonate or magnesium carbonate. This ingredient is quite useful in gardening because of its ability to neutralize soil acidity and filter harmful substances from the soil.
Silica is the next important component, vital for plant growth and development. Silica improves cell strength and cell structure rigidity. The result is greater pathogen resistance and enhanced metabolic function of plants.
Quartz or quartzite is the last ingredient. The former is man-made, and the latter is natural. This ingredient helps keep the soil together and prevents it from being washed away. Quartz is basically a metamorphic rock formed by interlocking mosaic quartz crystals.
Where to get one?
This might be the simplest answer of them all. You can find it in Walmart, order it from Amazon, or source it from a local farm supply store. The cheapest one you can get is poultry grit.
Another option is to go to the local rock/stone center and ask for granite grit for your garden. These are small angular-shaped stones that are crushed.
Pros and Cons
As with every product, there are always benefits and disadvantages of using it. With that in mind, let’s talk about the pros and cons of using horticultural grit. This product offers some unique benefits, making it a great fit for any gardener out there who wants to optimize plant growth and improve the soil.
- Makes the soil less compact
- You can buy either lime-free or products with lime for better control of the soil’s pH level
- Dries out quickly
- Grit is inorganic
- It is long-lasting
- Improves aeration and drainage of the soil
We cannot talk about many cons of using grit. The main problem is the high price compared to the individual material it is made of. But the price goes up because of the washing treatment. That whole process makes horticultural grit much more expensive than the individual materials.
How to use it?
We are now at probably the most important part of the article. How to use it? Is there a dosage? Instructions?
Generally speaking, you should use 50g of horticultural grit for every 1l of soil. It delivers the best compromise between drainage and weight of the overall soil volume.
Mixing is the easy part. The hard part is understanding which plants need more drainage than others. This is where your talent as a gardener comes in. The general rule is that succulents and cacti prefer a grittier soil mix. They do not require much water. Indoor plants, on the other hand, need more drainage to prevent instances of overwatering.
Adding this type of grit to your compost can stop the soil from sticking together and enable excess water to drain away.
Grit is quite popular with alpines. These plants typically grow in rocky soils and sunny locations. You can easily replicate those conditions with containers and grit. For planting alpine, use equal parts of compost and grit. Fill within 12cm of the container’s rim, then level off around your plant and finish with an even top layer of grit.
Horticultural grit vs. horticultural sand
You probably hear these two terms all the time. They are quite similar, yet different. The main difference is in the particle size. Those of grit range between 1 and 6mm, making them larger than those of sand.
On the other hand, horticultural sand is coarser and with larger particles than beach sand. Despite the differences in size and other things, both function in the same manner. Their main goal is to improve drainage and aeration in the soil.
Both sand and grit are mixed with soil to loosen it, allowing the roots to penetrate and for water to drain unimpeded.
The terms are used interchangeably. Some would say grit is the term used in Europe and Australia, while the term horticultural sand is mostly used in the US. No matter the confusing naming scheme, the properties of the product are the same.
Grit vs. Sharp Sand
Now here is another comparison. Grit has coarser and larger grains than sharp sand, which means it helps with gardening more. Sharp sand is primarily used for construction, hence the common name builder’s sand.
But if you are working with a larger space, you can use it. It is a much cheaper choice. But remember, it is not as effective as horticultural grit.
Do not use sharp sand for indoor gardening. This type of sand is often washed away meaning it has some silt and clay content in it. It makes it less optimal for gardening.
Decorative use of horticultural grit
Yes, you can use grit as a decorative tool. Besides its practical use of improving soil structure, horticultural grit improves the aesthetic of the soil and pot as well.
You can use lighter colors of the crushed stone that will contrast nicely with the dark and earthy tones of the soil.
You can use it to create distinct, multicolored, and multi-textured layers.