Got some builders sand you need to use up? Or maybe you have seen the difference in price between agricultural sand and builders’ sand and you want to know if you can save a bit of brass?
Yes, you can use builders’ sand in your garden, the coarse nature of builders’ sand actually makes it ideal for use in the garden.
Sand is often used in the garden to improve soil drainage. It helps to break apart heavy soil which then allows water to drain through it easier.
If you have really heavy clay soil, then you should be adding a sand and compost mix on top of it rather than trying to mix it in.
There is horticultural sand available which is specifically designed to be used for this purpose, but it is often more expensive than builders’ sand and at the end of the day, sand is sand, right?
Well, not always, I wouldn’t recommend using something like play sand, designed for children’s sand pits, as this is really fine sand and can sometimes make the problem worse.
Coarse builder’s sand has larger pieces in it, which actually makes it perfect for improving the soil.
What Makes Builders Sand Different?
Builders’ sand is meant for construction projects, it is mainly used for bricklaying as it allows for a smooth finish when making mortar.
Horticultural sand is normally quite coarse and is usually coarser than builders’ sand, this is what makes it better for improving drainage.
What you can do though is mix a bit of small grit in with your builder’s sand to make it even better at improving drainage.
Sharp sand is also sold by builder’s merchants and is usually the sand you mix into cement and concrete mixes. Buy washed sharp sand just so there are no nasties in there.
Sharp sand also has the advantage of being one of, if not the, cheapest sand you can buy in bulk.
Uses For Sand In The Garden
So now that we know that you can use builders’ sand in the garden let’s look at why you would want to in the first place.
Improving Heavy Clay Soils
As I mentioned earlier, adding sand to heavy clay soils helps to break them up and improve drainage. This is probably the main reason for using sand in the garden.
The best way to go about this is to also add compost and organic matter like manure at the same time. If you just add sand to your clay soil it can sometimes turn rock hard, almost like concrete!
Mix some sand, compost and manure into heavy clay soil, and you will soon improve that soil. If your clay is really heavy, then it can be tough to mix anything into it in the first place.
In these cases, I recommend using raised beds and getting really good soil on top of the heavy clay base soil. You can achieve the perfect soil mix with those three ingredients I mentioned earlier. Compost, sand and some organic matter.
The organic matter could be cut grass, manure, leaves, leaf mould, or anything that is breaking down. This helps to improve the soil as it provides nutrition as it breaks down but not only that it leaves air pockets as it breaks down which prevents your soil from becoming overly compacted.
I don’t recommend using bark here (use it sparingly if it is all you have!) because bark takes a few years to break down and while it is actively breaking down it actually steals nitrogen from your soil.
If you have too much bark in the mix that is still breaking down, then it will harm the growth of other plants in that soil.
Cuttings
Some plant cuttings take a lot better in a sand mix than they do in compost. Good drainage helps promote root growth by providing lots of room for air circulation, which is crucial for root development in a lot of plants.
Potting Mix
Potted plants often struggle with poor drainage, which is where adding a little sand comes in. You can add a layer of sand to the bottom of your pot or mix it into your potting mix.
What Can You Use Instead of Sand?
Looking for alternatives from sand to use in your garden to reduce soil compaction and improve drainage, then here are a few ideas for you.
Vermiculite
This is a rock-based mineral that is commonly used in horticulture, you will find it used in house plants a lot and also pre-mixed into some commercial composts.
Vermiculite helps with water retention as it is super absorbent but also breaks up the soil making it generally lighter and better for plant growth.
Bark
Bark can be used to break up the soil but as I mentioned before it does take up nitrogen as it breaks down so it can make for poor growing conditions if overused. One advantage of using something like bark is that it leaves lots of air pockets in your soil as it does break down.
This helps reduce soil compaction and also helps improve airflow which stimulates root growth.
Bark also works as a mulch and help keeps weeds from being able to grow and establish themselves.
Gravel
Good old gravel, will do what gravel does and allow for easy water flow in your soil and stop it from forming together in sticky clumps which prevent water from escaping.
Coir
This is essentially the furry skin from coconuts, it is used as a hanging basket lining but also more and more as a peat replacement in peat-free composts.
You can buy it pure and add it to your soil and compost yourself. It helps improve drainage and reduce soil compaction and is obviously a 100% natural product that can also be organic depending on where you get it from.