Strong, healthy plants need good topsoil. But it your garden isn’t well established, your soil may not have the nutrients your plants need. And quality topsoil can also be eroded by the wind or rain. So how do you put that right without spending a fortune?
That’s where we come in! We’re going to tell you how much you can expect to spend on topsoil. And we’ll give you some great tips to save money, whilst still getting excellent results.
So let’s get started!
How much should you spend on topsoil?
The cost of topsoil can vary widely by type and supplier, so shop around. Remember to take into account delivery charges too.
If you’re buying a large quantity, it will be very heavy and take up a lot of room. Unless you have access to a flatbed or pickup truck, you’re unlikely to be able to transport it yourself.
For smaller quantities, a car may be able to do the job, depending on how it’s packaged. But even larger cars may only be able to fit in enough topsoil for a corner of your garden.
Topsoil cost per tonne
Setting aside delivery costs, topsoil prices vary from £20 to over £80 per tonne. And if you want smaller quantities of enriched topsoil, suitable for plants or vegetables, you can be looking at around £80 per half tonne.
With such a lot of variation, you want to know that you’re getting the right product at the right price.
How do you know what kind of topsoil you need?
The amount of information available about topsoil varies widely by supplier. Generally speaking, the more specific the information, the higher the price.
If you have particular needs, you may need to invest in a premium product. There’s no point purchasing cheap topsoil, then finding that your vegetable patch is full of nothing but weeds! You’ll only have to spend the money on soil improver instead. And you’ll be making extra work for yourself.
But if you just need to raise the level of part of your garden – perhaps to lay a path or patio – you may not need topsoil at all. Inexpensive subsoil will be fine if you don’t have to grow anything in it.
There are some excellent deals available on online websites, often with soil that has been excavated from building sites. But just make sure you’re not buying subsoil at topsoil prices.
If you need a smooth, flat surface, or want to grow more delicate plants, look for topsoils that have been screened. That simply means that the soil has been passed through a mesh to get rid of stones and other objects.
You can, of course, screen the soil yourself if you want to save money. But beware before you embark on this – it’s backbreaking work, even for smaller quantities.
How do you know that you’re buying quality topsoil?
Buying from a reputable retailer is a good starting point to ensure you’re getting a quality product. But there are other things you can do too.
The first it to ask to see certification. There is a British standard for topsoil – BS3882:2015. In order to meet it, the soil must be free from contaminants and debris.
Note that meeting the standard won’t tell you what the soil contains. Anything from low-nutrient topsoil for growing wildflowers to enriched soils for fruit and vegetables can meet the standard. So you’ll still need to check that it’s suitable for the use you have in mind.
And if you’re able to, take a look at the soil before you buy it. Check that it’s a dark, rich brown and doesn’t have any nasty smells. Run your fingers through it to check it doesn’t contain debris like rocks, brick fragments or large roots.
And check the texture too. You don’t want anything that’s either too dry and sandy, or that sticks together in one big lump. If you can work it lightly between your fingers, your plants’ roots will be able to get a good grip too.
Purchase the right amount
Avoid spending more than you need to by purchasing the right amount of topsoil. But don’t skimp. Delivery can be expensive. You don’t want to have to pay for it twice if you find you don’t have quite enough.
You may also find that you can get a discount if you’re purchasing larger quantities. It’s always worth asking. And many suppliers reduce the cost per tonne as order sizes increase.
Calculate the amount of topsoil you need by measuring the width and depth of the area you’re covering. If it isn’t a convenient square, you can map the shape onto a grid.
Draw it as near as possible to scale. Use graph paper if you have some, or draw a grid on top. Make each square of the grid or graph paper cover one square metre (or yard, if you prefer Imperial).
Then count up each square that’s filled by your drawing. Count squares that are at least half-full of garden on your drawing, and ignore any that are less than half-full. That will give you the required surface area. Because it won’t be exact, we’d recommend adding 10 to 20 per cent extra.
Now multiply the surface area by the required depth. That will give you the volume you need in either cubic metres or feet, depending on your preferred unit.
If your supplier provides their topsoil in tonnes – as most do – you’ll now need to convert that volume to weight. One cubic metre of topsoil can weigh between 1 and 1.7 tonnes, depending on how much moisture it contains.
That’s a big range, making it easy to order the wrong amount. The best way to deal with this is to use a supplier that offers an online calculator. These allow you to input your measurements and will automatically calculate how much topsoil you need.
They will even tell you how many bags you should order. It’s a lot easier than trying to work it out yourself. And because the calculation is matched to the density of the topsoil they provide, you’ll get much more accurate results.
Deciding on the depth of your topsoil
Calculating the right amount of topsoil for your needs includes deciding how deep it will go. And that can vary a lot, depending on your garden and requirements.
If you’ve already got some decent soil, take that into account when you measure. You’ll only need enough topsoil to top up what’s there already.
The amount of topsoil you need will also depend on how you’re using it. Laying turf or sowing grass seed generally requires about 10 centimetres of topsoil. For plants or vegetables, you’ll need enough to accommodate the longer roots. That’s usually between 30 and 45 centimetres.
Again, don’t buy more topsoil than you need. If you’re planning raised beds, the whole thing doesn’t have to be filled with topsoil. Subsoil, inverted turves or even rubble can be used to fill the bottom. As long as your plants’ roots aren’t going to be touching it, it doesn’t matter.
Reuse what you have already
Unless you’re on a newly developed site, you’ll have some kind of topsoil in place already. If you’re building raised beds, remove the topsoil from the area where the beds will go. But keep it safe! You can build up your beds with subsoil, then reposition the topsoil you removed on top.
The same goes if you’re excavating an area, say for a pond or foundations for a shed. You’ll be able to see the difference between topsoil and subsoil very easily. The topsoil is the stuff nearest the surface, and it’s a darker, richer colour than the subsoil.
Take care as you’re digging out the area and keep the topsoil separate. Sieve it through to get rid of stones, debris, and to break down any large clumps. You can make your own sieve by attaching wire mesh to a wooden frame. But note that it takes a lot of time and effort to get a reasonable quantity.
Save money with community spirit
If you’ve found a good deal but the minimum order is more than you need, consider sharing with others.
Remember that you’ll need to be able to transport the topsoil to anyone who needs it. That can be hard work, so it’s probably only a realistic option to share with neighbours. But if you’ve got a wheelbarrow and neighbours who want to chip in, this can be a good option.
Make sure you know where and how your topsoil will be delivered. If it’s going to be in bags, you may be able to sweet talk the driver into delivering some a few doors along – but don’t rely on that. You may need to shift them yourself.
And if the soil is going to be delivered loose, be sure to have somewhere appropriate for it to be unloaded. That community spirit will evaporate fast if your neighbours find a tonne of topsoil spilling onto pavements or roads!
Ready to buy your topsoil?
We hope you’ve enjoyed our guide to the cost of topsoil. And we hope our tips will help you save money!
Always buy from a reputable supplier, and take the time to calculate exactly how much you need. Don’t forget to use what’s already in your garden. And remember that sharing a larger order with a neighbour can help you get a good deal.
Good luck with your purchase!