Garden products you don’t need (and what to do instead)

Garden centres are wonderful places. It is very easy to spend a morning wandering around one and, before you’ve even looked at a plant, you have a trolley full of products that promise to solve problems and fix deficiencies you don’t even have.

This isn’t an argument against spending money on your garden. Quality tools, healthy plants, and the occasional bag of something genuinely useful are all worthwhile investments. But the gardening industry is as commercial as any other – it’s big business and it’s blooming, tapping into every trend out there in a quest to sell us a convenient, beautiful dream. The market is packed with products that range from mildly pointless to actively counterproductive.

Here are the products you can confidently leave on the shelf, along with some thoughts on what to do instead. Most of the alternatives here involve doing less, spending less, and trusting nature a little more. Work smarter, not harder!

1. Mycorrhizal fungi inoculant

Mycorrhizae are fungi that form symbiotic relationships with plant roots, increasing nutrient and water availability by extending the effective root system, as well as protecting the plant from a variety of stresses. It is a genuinely special relationship, but it happens naturally without any intervention from you. Mycorrhizal fungi are already in your soil and have been there for hundreds of millions of years. This is one of the most widespread and ecologically important mutualisms on earth, and evidence suggests it’s one of the reasons plants were able to colonise land in the first place.

The products sold in garden centres contain dried fungal spores that are supposed to colonise your plant roots at the point of planting. But most garden soils already contain native mycorrhizal species that are far better adapted to your local conditions than anything from a packet. If your soil is healthy, the fungi will find your plants entirely on their own.

The best thing you can do for the mycorrhizal networks in your garden is to stop disturbing them. Dig less, avoid synthetic fungicides or herbicides, keep the soil covered with mulch, and let the biology do what it has been doing since long before garden centres existed.

2. Compost activators

Compost activators in powder, liquid, or pellet form are meant to be added to your compost heap to ‘get things going’. The claim is that they introduce or boost the microbial activity needed to break down organic material. Some also contain nitrogen, which is one of the key constituents of a healthy compost heap.

However, a compost heap does not need a bought activator. It needs four things: green material (nitrogen-rich stuff like grass clippings, vegetable peelings, and fresh weeds), brown material (carbon-rich stuff like cardboard, straw, dry leaves, and woody prunings), moisture, and air. As long as those things are present, it will break down perfectly well on its own.

If your heap is slow, the issue is almost always one of balance. If there are too many browns, you can add some grass clippings or kitchen scraps. If it’s too wet and smelly, you can add more cardboard and turn it. If it’s too dry and doing nothing, just water it. You don’t need to buy anything, just make these minor adjustments as you go along. If you want a genuine activator, just collect your (nitrogen-rich) pee and pour it on the heap every day. It’s very effective and costs nothing!

3. Bone meal

Bone meal has been a fixture of gardening advice for generations, particularly when it comes to planting bulbs. The recommendation to throw a handful into every planting hole is repeated so often that we never think to question it. The reality, though, is that most gardens simply do not need it.

Bone meal is a phosphorus fertiliser, processed from animal bones. Phosphorus is a nutrient that plants do need, but it is one of the most abundant nutrients in most soils, and it does not leach away the way nitrogen does. Decades of garden feeding have left many soils with more phosphorus than they actually need. Adding more does not help the plants; in fact, excess phosphorus in the soil actively suppresses the mycorrhizal networks that help plants access other nutrients. Applying it undermines one of your soil’s most important biological systems.

If you’re convinced your soil needs additives, get your soil tested by a lab. If your phosphorus levels are already adequate, as they are likely to be in almost any garden, there is no benefit to adding bone meal. Bulbs in particular are very well adapted to finding their own nutrients; in fact they contain their own food supply in the form of the bulb itself.

4. Fish fertiliser

Fish fertiliser – liquid feed or dried meal – has a devoted following among gardeners who feel that its organic, natural origins make it of particular benefit. The marketing leans heavily into this, suggesting that the proteins, amino acids, and trace elements in fish products do something that other fertilisers cannot.

In practice, plants cannot absorb proteins or oils directly. Those compounds have to be broken down by soil microbes into basic mineral nutrients first, at which point they are chemically identical to the same nutrients from any other source. Fish fertiliser is not bad, but it’s not doing anything that a good homemade compost cannot do just as well.

Fish fertiliser is one of the most expensive ways to buy nitrogen, often by a considerable margin. If you are making your own compost and using it consistently, you are already providing your soil with a balanced, slow-release source of nutrients that no bottle of fish extract can match for value. If you feel your plants need a liquid pick-me-up during the growing season, a homemade comfrey feed – made by stuffing a bucket with comfrey leaves, weighing them down, covering with water, and waiting a few weeks – is free, effective, and rich in potassium.

5. Bloom-booster & high-phosphorus fertilisers

Fertilisers marketed as ‘tomato feed’, ‘flower booster’, or ‘big bloom’ boast a high phosphorus content and promise more flowers, bigger fruit, and richer colour. They are very heavily marketed during the spring and summer, and they sell in enormous quantities.

The phosphorus angle, as discussed above in the bone meal section, is a problem in itself. But there is a secondary issue with these products that makes them particularly counterproductive for anyone interested in a biodiverse, living garden. Excess phosphorus in the soil does not just sit harmlessly; it actively inhibits the formation of mycorrhizal associations. The mycorrhizal fungi that help your plants access water and trace nutrients (see the first entry above) are suppressed when phosphorus levels are high, because the plant has no incentive to form the relationship. You are paying to make your plants more dependent on bought fertiliser and less capable of looking after themselves.

Fruits and vegetables grown in compost-enriched soil and given a homemade comfrey or nettle feed during the growing season will perform just as well without any specialist bloom booster. Flowers in the ground rarely need feeding at all, particularly if the soil has been mulched and/or compost is applied annually.

6. Bought worm castings

Anyone who composts can tell you that worm castings – the material produced by worms as they process organic matter – are amazing. Rich in available nutrients, they contain beneficial microbes and have a fine, crumbly texture that is ideal for seed sowing and potting. Bought worm castings, though, are expensive, and there is absolutely no reason to buy them when you can produce them at home using waste.

A worm bin – which can be made from an old wooden box, a plastic storage crate, or a stacking system made from second-hand buckets – will process your kitchen scraps into rich castings continuously throughout the year. The worms themselves are cheap to buy as a one-off, and once established, the bin runs itself with very little intervention. The liquid that drains from the bin (worm tea) can be diluted and used as a liquid feed. It is one of the most satisfying closed loops in the garden.

7. Copper slug tape

Copper slug tape is sold as an environmentally friendly slug deterrent to be stuck around the rims of pots or along the edges of raised beds. The theory is that slugs receive a mild electric shock when they touch the copper, discouraging them from crossing it. It is presented as a humane, chemical-free solution to slug damage.

The practical evidence for it working in garden conditions is weak. Slugs do show some aversion to copper in controlled laboratory settings, but in a real garden – with damp tape that quickly oxidises, debris and soil bridging the barrier, and slugs approaching from below the soil – the deterrent effect is minimal at best. Many gardeners who have tried it report no meaningful reduction in slug damage.

The more effective approaches are free or very cheap. Encouraging natural predators like hedgehogs, frogs, toads, ground beetles, and slow worms should provide all the biological control you need. If you have particularly vulnerable plants, going out at dusk with a torch and a bucket of salty water helps you remove slugs directly. The most durable solution is to grow a range of plants and accept that slugs will eat some of them, growing the most precious ones in protected conditions until they are large enough to fend for themselves.

8. Blossom end rot sprays

Blossom end rot is the black, sunken patch that appears on the base of tomatoes, courgettes, peppers, and other fruiting vegetables. It is a common and disheartening problem, and the conventional response is a range of calcium sprays that you apply directly to the fruit or leaves.

The trouble is that blossom end rot is not caused by a lack of calcium in the soil. It is caused by the plant’s inability to transport calcium to the developing fruit quickly enough, and that inability is almost always the result of inconsistent watering. When a plant experiences an irregular water supply – wet, dry, then wet again – its uptake of calcium is disrupted even when there is plenty of calcium available in the soil. Spraying calcium onto the leaves or fruit cannot fix this, because the problem is not a shortage of the nutrient but a disruption in the process by which it moves through the plant.

The solution is consistent watering – not necessarily more water, but more reliable water. Growing tomatoes in the ground rather than in pots or grow bags makes this easier, since the soil acts as a buffer against wet-dry cycles. Mulching around the base of plants helps retain moisture between waterings. If you are growing in containers, self-watering planters or a simple drip irrigation system can help enormously.

9. Tree wound paint & pruning sealant

Painting tree wounds has been an established arboricultural practice for decades. The idea seems sound: when you cut a branch, you expose the wood beneath to infection, so you should seal the wound the way you would seal a cut on your own skin. Pruning sealants are sold specifically for this purpose.

Research carried out since the 1970s has consistently shown that sealing tree wounds either makes no difference or actively slows healing. Trees don’t heal the way mammals do; rather than regenerating damaged tissue, they insulate from the wound, forming chemical and physical barriers around the damaged area to prevent infection from spreading inward. This process, known as compartmentalisation of decay in trees (CODIT), works best when the wound is left open to the air. Applying a sealant can trap moisture, prevent the wound from drying properly, and in some cases encourage exactly the fungal growth it was supposed to prevent.

The correct approach when pruning is to make clean cuts in the right places – just outside the branch collar, which is the slightly swollen area where the branch meets the trunk – and then leave the tree to manage its own response. A sharp, clean tool makes a better cut than a blunt one and is a far better use of your money than a tin of wound paint.

10. Insect & fly killers

Insect zappers – blue-lit electric devices that kill insects – are sold as a way to reduce mosquitoes and other biting or nuisance insects around outdoor spaces. They are also sold as an effective general pest control measure for the garden.

Unfortunately, multiple studies have shown that the insects most attracted to the ultraviolet light in bug zappers are moths, beetles, midges, and other species that are either harmless or actively beneficial. Mosquitoes, which largely locate hosts by body heat and carbon dioxide rather than light, are poorly represented in what these insect killers actually catch. Such a device positioned in your garden on a summer evening will be killing important pollinators and food sources for bats and birds while doing very little to the species actually causing a nuisance.

For biting insects, the most effective strategies are situational: not sitting near standing water in the evening, using a fan outdoors (which disrupts the insects’ ability to track you), and wearing appropriate clothing. For the garden as a whole, encouraging insectivorous birds and bats is far more effective for managing insect populations than any electrical device and has the considerable advantage of improving rather than depleting the local ecosystem.

11. Pheromone traps

Pheromone traps use synthetic versions of insect sex pheromones to lure specific pest species – codling moth, vine weevil, and various others – into a sticky trap. They are a targeted, chemical-free way to monitor and control pest populations, and they do have legitimate value as monitoring tools: catching a few individuals tells you that the pest is present and active, which can inform your timing for other interventions.

The problem comes when they are used as a control method in a typical garden, because the science of pheromone trapping suggests they work best at scale. In a large commercial orchard, trapping can make a meaningful dent in mating success and reduce pest populations. In a small garden surrounded by other gardens, hedgerows, and fields, what you are more likely doing is attracting insects from a wider area, catching some of them, and actually increasing the local concentration of the pest rather than reducing it.

For most common garden pests, cultural methods like good sanitation, removing damaged fruit, growing a diversity of plants to encourage predatory species, and accepting some level of damage as normal will serve you better than traps. If you do want to monitor for a specific pest, a single trap used purely to understand whether and when the pest is active is a reasonable investment. Using them as a control tool in a small garden is magical thinking.

12. Deer & rabbit repellent sprays

These sprays are usually based on compounds that smell or taste unpleasant to animals, such as garlic, chilli, or putrefied egg, and are marketed as a way to discourage deer and rabbits from eating your plants. They are popular, widely available and, in a garden where rainfall is reliably frequent, not particularly effective because the active compounds wash off.

In wetter climates, re-application is needed so frequently that the cost and effort of keeping up with it become their own argument against the product. The animals also habituate to the smell over time, particularly if food is scarce.

Physical exclusion is the only reliable answer. For rabbits, a wire mesh fence buried at least 30 cm into the ground and bent outward at the base will prevent burrowing. For deer, the fence needs to be at least 1.8 metres high. Individual tree and shrub guards will protect specific plants during their vulnerable early years. For vegetable gardens, a fruit cage or mesh tunnel keeps rabbits and most birds off the crops without any need for spraying. These solutions require upfront effort and cost, but they work continuously and do not need to be constantly reapplied.

13. Cheap electronic soil pH meters

These are small devices with a metal probe that you push into the soil to get an instant pH reading. They look reassuringly scientific but are completely unreliable. The cheap versions are simply not accurate enough to give a reading you can act on with any confidence. Meters that actually work cost hundreds of euros, even thousands, and are therefore an unnecessary purchase for the typical gardener.

PH affects the availability of key nutrients and therefore how well certain plants will get on. Acting on an inaccurate pH reading means you’ll adjust incorrectly, which could waste money and has real consequences for plant health. You can send soil samples to a lab for accurate testing if you are planning to include fussy plants in your garden. But pH is only one indicator of whether a plant is likely to thrive.

Instead of testing pH, use your observation skills to better understand your growing conditions. Talk to long-time residents about the local soil and observe what is thriving in neighbouring gardens as well as in wilder spots like ditches and hedgerows. You can cross-reference what you are seeing with the indicator plants in your part of the world. The great thing about this method is it won’t just show you whether your soil is more acidic or more alkaline, but also help you spot areas where soil is compacted and low or high areas of fertility.

14. Sunlight calculator gadgets

A sunlight calculator is a small electronic sensor that you place in a spot in your garden, leave for a period of time, and then retrieve to get a reading of how many hours of direct sunlight that spot receives. They are sold as a tool for matching plants to the right conditions.

This is useful information, but you do not need a gadget to get it. The movement of the sun is predictable, and you can map the sunny and shaded areas of your garden simply by observing it at intervals over the course of a day – say, at nine in the morning, noon, three in the afternoon, and six in the evening. A rough sketch of your plot with notes on shade at each time of day will tell you everything the sensor can tell you, and it will tell you how conditions change across the seasons if you repeat it a couple of times through the year. It costs nothing and takes twenty minutes, and you will learn more about your own garden in the process. There are also great websites like Shademap that can give you a head start on your observations.

15. Proprietary seed-starting kits

Every spring, garden centres and seed catalogues offer seed-starting kits: a tray, a propagator lid, some small modules, and sometimes a heating mat or a small bag of specialist compost. They are marketed as everything you need to get started in a convenient, matching set.

A kit is useful if you have no equipment at all and have never grown from seed before. But the individual components are either unnecessary (specialist seed compost can be made at home by sieving your own compost or mixing peat-free compost with sharp sand), freely available from your recycling bin (any shallow container with drainage holes works as a seed tray), or something you only need if you are growing heat-loving plants very early in the season.

A south- or west-facing windowsill in late February or March is warm enough to germinate most seeds without a heated propagator. A sheet of glass or some cling film placed over a seed tray maintains humidity during germination just as well as a proprietary lid. Seeds started slightly later, without any artificial heat, will catch up with earlier-sown ones within a few weeks, because they come into growth as the days are already warming and lengthening. Kits are largely selling you equipment to compensate for starting too early.

16. Plastic plant labels

Bulk packs of plastic plant labels are cheap, but not cheerful. The plastic becomes brittle quickly in UV light and easily fragments into little pieces that end up in your plant beds. They are easily replaced without buying anything at all.

Lolly sticks, ceramic tiles, paint stirrers, old spoons, stones, tin lids, timber offcuts, slate roofing tiles, shells, terracotta pots, wine corks, clothes pegs, and sticks with the end whittled smooth are all great surfaces for writing on and cost little or nothing. Permanent marker isn’t your best option for writing, however. Try paint markers or chalk markers on stone, slate, and ceramic; pencil, paint markers, or a pyrography pen on wood; and metal stamps or paint markers on metal. Experiment with different materials and techniques and make your labels decorative as well as informative.

17. Grow bags

Grow bags are sold specifically for tomatoes, peppers, cucumbers, and other fruiting crops. The idea is you plant straight into a slit in the bag rather than needing beds – getting you growing instantly.

The compost in a standard grow bag is adequate but not deep. The volume is too small to support large plants through a full season without very frequent watering and feeding; the bag heats up and dries out rapidly in warm weather; the plastic degrades in sunlight and tends to split; and the low profile means the root system has nowhere to go. Plants grown in grow bags frequently suffer from the inconsistent moisture levels that cause blossom end rot in tomatoes and other stress responses in fruiting crops.

Growing in the ground – even in a small, crowded bed – gives roots the depth and volume they need, the buffering effect of a larger soil mass against temperature and moisture fluctuations, and access to the soil biology that exists in the ground but not in a bag. Where space is genuinely limited and growing in the ground isn’t possible, a large container – a half-barrel, a deep raised planter, or even an old dustbin with drainage holes drilled in the base – will perform far better than a grow bag and can be reused year after year with fresh compost added. If you make your own compost, the economics of this are clear.

18. Landscape fabric/weed membrane

Landscape fabric (also called weed suppressant membrane, geotextile, or ground cover fabric) is one of the most widely used and most damaging products in mainstream gardening. It is sold as a solution to weeding: lay it down, cut holes for your plants, cover it with bark or gravel, and the weeds will never come back.

It does not work long-term. Within a season or two, organic material – leaves, debris, and bark mulch – begins to accumulate on the surface of the fabric, and weed seeds move in and germinate. Their roots grow down through the fabric, and when you try to pull them out, the fabric tears. Within a few years, most landscape fabric installations are worse to manage than bare soil would have been, with weeds anchored through the membrane. Landscape fabric also prevents water from moving freely through the soil profile, reduces the ability of earthworms and other soil life to travel between the surface and deeper layers, stops organic matter from reaching the soil where it can feed the biology, and degrades into microplastics that persist in the environment indefinitely.

The alternative is a thick mulch of organic material, like wood chip, straw, or wool, laid five to ten centimetres deep directly on the soil surface. This suppresses annual weeds effectively, feeds the soil as it breaks down, retains moisture, and improves soil structure over time. You’ll have to reapply it every year or two, but you’ll know that in decomposing it has benefited your soil immensely!

19. Mass-produced insect hotels

The insect hotel has become a fixture of environmentally aware gardening, and the intention behind it is a worthy one. Many solitary bees and other beneficial insects need specific nesting structures – hollow stems, loose bark, bundles of dead wood – and providing these structures in the garden is genuinely worthwhile.

The problem is with the widely available mass-produced versions and their tightly packed chambers stuffed with pinecones, bamboo tubes, and blocks of compressed wood shavings. They look cute, but many of these products do not provide usable habitat for any particular species, with incorrectly sized and unattractive micro-habitats.

Valuable insect habitats require little money, if any. A bundle of hollow-stemmed plant material – lovage, teasel, meadowsweet, cow parsley, hogweed, fennel, sunflower, goldenrod and hollyhock offcuts of about 20 cm in length – tied together and mounted facing south-east in a sheltered, sunny spot will attract solitary bees far more reliably than any commercial hotel. A pile of logs left in a damp corner provides habitat for beetles, centipedes, and fungi. A patch of bare, south-facing soil left undisturbed is the most important habitat of all for the majority of ground-nesting solitary bees, which do not use above-ground structures at all.

20. ‘Pollinator’ seed bombs & wildflower mixes

Seed bombs are small balls of clay, compost, and seeds, sold as an accessible, joyful way to create wildflower habitats. Wildflower mixes in packets are marketed along similar lines, promising to transform a bare patch of garden into a buzzing, biodiverse meadow. Both have become enormously popular, but both require a degree of caution.

The issue is not the concept, but the contents. Many commercial wildflower mixes contain species that are not native to the country they are marketed to, containing a mix of prairie flowers and ornamental cultivars from around the globe. They look great but contribute little to the food webs that native insects, birds, and other wildlife depend upon. Many mixes are padded out with annual species that will disappear after the first year if not re-sown.

Native wildflower seeds from a specialist supplier are a better starting point, and better still is to allow blow-in seed to colonise your garden – as local seed carries genetic material that is specifically adapted to your regional conditions, climate, and soil. The best wildflower areas in most gardens begin with reducing fertility (scraping off topsoil, or simply mowing short and raking off the clippings for several years) and allowing plants to establish from the soil’s existing seed bank. This produces a genuinely local plant community.

On a related note, wildflower meadow ‘growing medium’ is also a pointless purchase. Wildflowers are adapted to conditions of low nutrient availability. Selling enriched growing compost for wildflower growing is selling the exact conditions that wildflowers cannot thrive in. To create better conditions for wildflowers, remove rich layers of topsoil, and don’t add compost or mulches in those areas.

21. Seasonal lawn feed subscriptions

Subscription services deliver a different lawn fertiliser for each quarter of the year: a spring formula for growth, a summer formula for heat resistance, an autumn formula for root strengthening, and sometimes a winter formula for frost protection. These seasonal-treatment models are a very effective way to sell four products where none are strictly necessary.

For anyone interested in a garden that supports wildlife, the quarterly feeding regime is counterproductive. Nitrogen-rich fertiliser promotes the rapid growth of coarse, vigorous grass species, which outcompete the finer grasses and the low-growing plants that naturally establish themselves in an unfed lawn, like clover, self-heal, daisies, bird’s foot trefoil, yarrow, and plantain. These are not ‘weeds’ but native flowering plants that support pollinators, provide seeds for birds, and create a far more interesting and resilient carpet. Grass-only lawns are a dysfunctional monoculture. For a biodiverse lawn, mow regularly (and remove the clippings to reduce fertility) and over-sow with a native planting mix.