Compost is fundamental to the history and future of humanity. It provides the nutrients plants require to thrive, maintains soil structure, and recycles organic matter, keeping the cycle of life churning. As such, it's something that every gardener should have in reserve, ready to add to their soil when required. But what kind of compost should you purchase, and how can you find the best compost prices?
This hotukdeals buyer's guide will explain everything you need to know. We'll look at what compost is, and how it is made, and explore how to find the cheapest compost around and the best compost deals. But first, it's time for a quick journey into the past, to find out where this magical material comes from.
Few products on the market are as old as compost. Ever since people have grown crops, they have tended to add some form of organic supplement to fertilise the soil and encourage crop growth. In many cases, that meant using “night soil” (human waste), or mixtures of animal waste.
In other, more sophisticated setups like the Mesoamerican “milpa” system of water-based agriculture, all sorts of composts were created and used to build artificial, hyper-fertile islands. In any case, without replacing nutrients in the soil, humans wouldn't have made much progress in producing the food required for civilisations to grow.
Specially produced, scientifically formulated compost is much newer. Modern gardeners can't really add animal waste directly to gardens, for health reasons alone. And as the Industrial Revolution took hold, chemical alternatives became dominant, displacing old-style composting.
However, this sparked rebellious growers into action, leading to the development of a totally new generation of composts. Starting in the 1920s, European organic farmers embraced sophisticated new composting systems which took food waste, digesting it over the winter months, and producing concentrated solutions. Elsewhere in the world, agronomists embraced composting to rebuild shattered soils that had been left vulnerable by years of chemical fertilisers and mechanised agriculture.
By the 70s and 80s, people around the world were recycling kitchen scraps, and purchasing specialist composts instead of industrial fertilisers, and this has only grown. Now, with the rise of organic food, permaculture, and widespread awareness of climate change and the need to consume fewer resources, composting is very much a mainstream activity.
In a sense, compost isn't a product. It's a process. When materials are composted, they are broken down over time by aerobic bacteria (which only thrive in the presence of air). This results in materials that are rich in carbon and nitrogen – elements which most plants require to grow.
If you're wondering how compost is made, the answer is that techniques vary. We'll discuss different types of compost in a moment, but the process has some common features. For one thing, organic materials need to be used as the basis for composting. So kitchen scraps (and even toilet waste in some cases) can be used.
Organic matter can then be mixed with carbon-rich materials like straw or grass, along with water – producing the conditions for bacteria to get to work. After that, the mixture needs to be aerated – adding oxygen to the organic material. If the mix is maintained correct, within 1-2 years a nutrient-rich product emerges.
Various options are available for speeding up the process or adding specific compounds to the mix. Worms can be used (vermiculture), as well as the larvae of the black soldier fly, and Japanese methods also use fermentation via lactobacilli (the type you find in many yoghurts).
Then there are applied methods of composting, which combine growing and composting in a single process. No dig permaculture and hügelkultur are two well-known methods, which result in extremely fertile beds that are ready for planting all kinds of plants and crops.
There are plenty of reasons to use compost on your garden. In fact, adding some form of soil additive should be a core element of virtually all planting strategies, as most soils tend to be degraded and far less fertile than they could be.
Fertility – The most obvious reason to use compost is that plants require nutrients, and compost delivers them. Composts vary greatly in their C/N concentrations (carbon and nitrogen), so check this before adding to your beds, as some plants can be sensitive to soil composition. And pH can come into the picture as well, changing the acidity or alkalinity of soils. Additionally, compost contains large concentrations of minerals that are often lacking from urban soils, including manganese and phosphorus.
Nutrient Release – Compost doesn't just contain nutrients. It also contains bacteria which release those nutrients. And the way they do so is really handy for gardeners, peaking in summer when the growing season is at its height, giving your sunflowers or potatoes the best chance of thriving.
Detoxification – Many urban soils contain dangerously high levels of heavy metals like cadmium (generally from batteries). When compost is added to soil, it chemically combines with these elements, taking them out of action, and away from plants, so they won't end up in your carrots or courgettes.
Water Retention – Healthy soil isn't just full of nutrients. It also has the ability to hold water instead of either repelling it so that it stays on the surface, or allowing too much to drain through to lower layers. Organic matter acts like a sponge, holding water close to the surface, where plants can easily access it.
Soil Structure – Compost helps to maintain a healthy soil structure, which assists plants in building their roots. It also attracts earthworms to work their magic, digesting organic material and converting it into nutrients.
Sustainability – The alternative to composting is using industrially produced fertilisers (which are generally made from the by-products of fossil fuel extraction). And by not composting, we also tend to throw away huge amounts of organic waste, which could be put to better use. So by adding compost to your soil, you will be doing the planet a favour.
As we've hinted at already, compost doesn't come in one generic format. Agricultural researchers have created plenty of different varieties, with properties that suit different plants and gardens. Here are the major types you'll find at hotukdeals:
Ericaceous Compost – This kind of compost is specifically targeted at flower gardeners, and especially those who love flowers in the Ericaceae family, which includes roses, camellias, gardenias, azaleas, and magnolias (so quite a lot of the most popular plants on the UK scene). This form of compost leans towards an acidic pH level, which suits ericaceous plants, allowing their petals to be as bold and bright as possible.
Peat-Based Composts – Derived from thousands of years of decomposition, peat is an incredibly fertile material, but it's a finite resource, so buyers should keep that in mind when purchasing peat-based composts. Often mixed with sand and vermiculite, these composts really suit carnivorous plants like flytraps, but won't be necessary for most gardeners.
Peat-Free Composts – Recently, companies have started replacing peat-based mixtures with similar blends that mimic peat, but use more sustainable ingredients like coir, wood shavings, and other agricultural waste.
Loam-Based Composts – An excellent alternative to peat-based composts, loam contains higher concentrations of clay and silt, and is often graded according to the nutrient concentration it contains. So, for instance, John Innes markets No. 1, 2, and 3 loam-based composts, with nutrient concentrations falling as you rise up the scale. Generally speaking, 3 is fine for outdoor planting, but 1 or 2 suits seeds & bulbs in greenhouses.
Multi-Purpose Composts – Generally peat-free these days, multi-purpose composts are the most popular variety around, mainly due to their versatility. They can be used for plant pots, hanging baskets, balcony tubs, outdoor vegetable gardens, or herbs in the kitchen, and tend to be very affordable when purchased in bulk. If you don't need specialist compost blends and just want to get started right away, check the hotukdeals' multi purpose compost deals and you'll be ready to plant in no time.
Organic Composts – Many composts are now labelled as “organic”, which means that all of their ingredients were produced without the use of artificial pesticides or fertilisers. Check for the Soil Association certification when buying, though. It's not unknown for brands to call their composts “organic” or “natural”, while cutting corners and adding inorganic ingredients.
Mulch – Mulch isn't compost, so don't get the two confused. But it can be essential to a healthy garden. Often coming in the form of bark chips, mulch sits on top of the soil, or dug into the upper layers, and provides a protective seal. This locks moisture in during periods of extremely hot weather, helps to protect against weeds, and also guards against some common pests. So it's usually a good idea to mix compost purchases with mulch if possible, and combo deals are often available.
Now that we've run through the uses of compost and some of the major varieties, it's important to make the right choice. Get this wrong, and you could actually damage your seedlings as they grow into flowers or shrubs, wasting money in the process. So here are some things to think about.
Always Choose Composts That Are Recommended For The Plants you Intend to Grow – When you choose a compost, check the labelling on your plants, or go online to search for recommended options. For instance, many buyers will be asking what compost for hydrangea they should use. In that case, gardeners will need an ericaceous compost to create the right pH levels. Plants vary, so be careful here, and use the hotukdeals listings to zero in on exactly the correct compost variety.
Think About Plant Lifecycles – Some composts are ideal for young seedlings, but won't be optimal for mature plants, and vice versa. Generally, seedlings prefer light composts that have small crumbs and won't stifle their development. Look for “seed sowing composts” for very young plants, and be careful about applying them around growing seeds.
Always Have Enough Compost for Your Containers – Many buyers will be looking to beautify their windowsills or balcony by growing flowers in containers. That's great, but you need to pick the right compost for containers before getting started. As a rule, composts that absorb water well are preferable, as dehydration is a real challenge for container growers. Varieties with clay granules should do the trick.
How Much Compost Do You Need? - Don't overbuy with compost. Remember, you can always add more at a later date if you find yourself running out. When applying compost, you'll need a blend of 40% compost to 60% soil (roughly), so use that as a basis to estimate the number of bags to purchase.
When picking a compost for sale at hotukdeals, it pays to opt for brands and retailers you can rely on. With the growth of organic gardening in recent years, plenty of deceptive products have emerged that won't do your garden much good. But these suppliers can be trusted to deliver the nutrients your plants require:
Wickes – As with most gardening essentials, Wickes produces its own range of composts, and they tend to mix value and quality in equal measure. Wickes compost focuses on multi-purpose varieties, and comes in 50l and 120l bags - with low prices for both options. A big benefit of buying from Wickes is that you can often use discount codes for compost, bark chips, topsoil, and other growing materials, and save money in the process.
Homebase – As with Wickes, compost at Homebase is a core product area, and the selection is pretty good. Unlike Wickes, Homebase doesn't make its own compost, but offers a selection of leading brands like Westland and J Arthur Bowers, with ericaceous and multi-purpose options available to buy.
B&Q – Another UK gardening giant, B&Q covers all of the options when it comes to compost. Buyers of compost at B&Q can pick up high-quality multi-purpose bags and compost additives which can turbo-charge growing in certain situations. Most products come from its associated brand, Verve, but Gro-Sure, Westland, and John Innes are well-represented.
Home Bargains – If you're looking for the cheapest compost around, and still want decent quality levels, Home Bargains compost is the way to go. Major brands like Westland and Growmoor are ready to order online, with all sizes of bag represented. And they are regularly halved in price, especially during peak growing seasons. As you'd expect, every Home Bargains compost deal can be found at hotukdeals.
Although we haven't really explored it yet, there is an important alternative to adding shop-bought compost to your soil: doing it yourself. Many people prefer to use their kitchen and garden waste to make their own compost blends, and it's not as hard as you might think, especially when you have the right kit on hand. Here are some essentials that home composters will want to get hold of:
Compost Kitchen Bin – These days, it's routine to see kitchen waste bins outside the back door of homes across the UK. If you haven't got one, these handy bins (which usually come in lockable flip-top configurations) are designed to hold around a week's worth of kitchen waste, and can be emptied straight onto compost heaps, or into council-collected bins if that facility is available. Brands like Addis make great bins. But always check for free kitchen compost bins, as many local authorities now provide them free of charge to encourage recycling.
Compost Digesters – To take your composting to another level, having a digester is essential. These containers are often simply mounted on rotating mechanisms, which need to be briefly churned on a daily basis. Able to hold large amounts of garden and kitchen waste, they mix up materials all the time, and provide the perfect setting for bacteria to thrive.
Outdoor Compost Bin – Many people will prefer classic compost heaps, as they allow easy maintenance and generate larger amounts of high-nutrient compost. These generally take the form of wooden containers, which look a little like palettes with fencing around the edges. You can actually build bins fairly easily by combining palettes, but it's usually better to buy from the experts, as if bins fall apart, the whole operation can be ruined. Alternatively, freestanding plastic bins are common, with an aperture at the top to throw in waste, and a slot at the base to extract finished compost.
Compostable Bags – These handy bags are essential for people who intend to recycle kitchen waste. When placed inside kitchen compost bins, they make it easy to transfer waste to digesters or outdoor bins, without making kitchen bins overly dirty. You can pick them up from major retailers like Home Bargains or Sainsbury's, but do so via hotukdeals to find the cheapest prices. There's no reason to pay more than you have to.
Composting is great news for your garden and the environment, turning kitchen waste into nutrients that flowers, herbs, shrubs, trees, and vegetables will adore. As we've seen, finding the right form of compost is essential, but doing so shouldn't be hard. However, it can be tricky to purchase high-quality compost at affordable prices, particularly if you need to buy enough to fertilise larger gardens.
Then again, there are solutions. At hotukdeals, gardeners in the UK can find affordable compost whenever they need it. Our listings include the cheapest compost from major retailers like B&Q, Homebase, Home Bargains, and Wickes, with brands like John Innes, Gro-Sure, and Westland all represented. You can pick up cheap compost for indoor growing, carnivorous plants, balcony tubs, and picky outdoor blooms. And it's easy to find compost bins and compostable bags as well.
If you shop outside growing season, you may be able to pick up even bigger bargains for next year's planting, but even when gardeners are at their most active, buyers will find excellent prices at the hotukdeals compost listings.
Whether you are growing a dazzling flower arrangement to amaze the neighbours, or you need to ensure that your allotment produces as much food as possible, compost is a gardening essential. Coming in a dizzying range of styles and brands, compost can also be a major gardening expense. But growers can easily cut the cost of tending their plot with the wide range of compost discounts at hotukdeals.
