Tips on buying topsoil.... Fantastic claims? It may pay to dig a little deeper.

When I studied geography at school topsoil was described as the thin layer of weathered material at the earth surface in which plants grew, if asked, most people would probably describe topsoil in a similar way. It's the natural earth under our feet, it's what we see in the farmer's fields, that's topsoil.. right?  Wrong.

There are topsoil suppliers out there (some well known) blending all sorts of different things and labelling the resulting product as topsoil, things like -

• Vegetable washings
• Sewage waste
• Skip waste
• Construction waste
• Sawdust
• Timber fines
• Slurry
• Quarry & mining spoil 
• River & canal dredgings

The resulting blends are marketed and sold as topsoil and I would guess that many customers believe they are buying natural topsoil, unaware they are buying nothing of the sort. The confusion in the market place can lead to suppliers making fantastic claims, for example, "up to 50% more product when compared with ordinary topsoil". This claim only works if you compare different things, but suggest they are the same.

So how can a supplier make such a claim? Easy, by blending two products together which are lighter than topsoil, let's say green waste compost and sawdust. Because the resulting mix is lighter than topsoil it could provide up to 50% more product. However, if we look at this from a different perspective it could be claimed that the natural topsoil provides 100% more topsoil than the green waste/sawdust mix.

Products being sold as topsoil which aren't really topsoil make it very difficult for buyers to compare like for like and without specialist knowledge it is almost impossible to make an informed decision. If your topsoil supplier is making fantastic claims, it may pay to dig a little deeper.

Tips on buying topsoil..... its all about asking the right questions

OK you're planning a new garden, you can see the finished image in your mind and you are reaching the point where you need some topsoil, maybe to reshape some flower beds, perhaps to fill in an old pond or re-level an area for a new lawn. Before buying, you need to ask the right questions.

What type of topsoil do I need?

The type of topsoil you need depends on your particular project. Different topsoils can be used for different jobs, for example if you're growing acid loving plants such as Azalea, Gardenia or Hydrangea you will need an ericaceous topsoil. If you're building a raised bed you might want to consider a friable, sandy loam with a neutral to alkaline pH. At this stage it's worth doing a little research into which topsoil is going to be most suitable for you. Talk to topsoil suppliers, talk with other gardeners, look online, visit blogs, ask questions. 

Where will the topsoil come from?

The quality of topsoil being sold in the market place can vary enormously. It's a sad fact that there are products out there being sold as topsoil that are nothing more than demolition and construction waste. Products that can potentially be toxic to the environment and human health. The old saying " buy in haste repent at leisure"  is worth remembering. Shop around, talk to different topsoil suppliers and again ask questions -

• Where has the topsoil come from?
• Do you have topsoil to meet my requirement?
• Is the topsoil a blend of different materials, if so what?
• Is the topsoil screened?
• Has it been tested?
• Do you have a test certificate?
• Can I come and look at the topsoil?
• Can you send me a sample?

Ask if the topsoil is a blend of different materials. Some products labelled as 'topsoil' are a blend of sand and composted green waste, some are a by-product of the vegetable washing industry. They may be a perfectly acceptable growing media, but it's worth checking exactly what you're buying. Check if the topsoil has been screened, you don't want to buy a topsoil full of large stones, rocks or flints.

It's a good idea to ask if the topsoil has been tested. The British Standard BS3882 (2007) is the bench mark for topsoil suppliers in the UK. Ask for a copy of a test certificate, make sure it's up to date. If you can go and have a look at the topsoil suppliers production facility, all the better, by looking around you will get a good idea if their topsoil is what you want.

Any reputable topsoil supplier will be able to answer your questions, will allow you to look at the topsoil they supply and will be happy to provide you with test reports and samples, if they can't, don't buy.