The best Substral lawn fertilisers, compared.
Top pick: Substral 7391 Iron Fertiliser Green – It has 4.6 from 848 ratings and the lowest shelf price in the set, about £15.35, as a liquid iron feed for lawns and other plants. Best value: Substral Express Sport & Game Lawn Fertiliser – At about £109.69 it is roughly £0.18 per stated square metre, the lowest in this set, only if you can use most of the 600 square metres during active growth. Updated October 2026.
A Substral lawn fertiliser, on these amazon.co.uk listings, is a granule or a liquid sold to feed lawn grass, sometimes with an iron, moss, weed or seed claim. If you want a dense all-grass lawn, spring is the usual time. The Royal Horticultural Society says a wildflower lawn should not be fed, and that many lawns cope without fertiliser. Drought and shade often explain weeds and moss better than a missed feed. Seven listings from 15 October 2026 are priced from about £15.35 to about £109.69. None of these titles is an autumn-only feed. Miracle-Gro, a seed-only pouch and a universal garden fertiliser were out of scope. This is not a laboratory trial. Comments labelled Reviewed in Germany are not UK review opinion. Substral 7391 Iron Fertiliser Green is the top pick on rating depth and shelf price. Substral Express Sport & Game Lawn Fertiliser is the best-value option only when you can use most of its stated 600 square metres during active growth. The [Substral lawn fertiliser buying guide](/hub/fertiliser-soil-and-bark-mulch/substral-lawn-fertiliser/sub/substral-lawn-fertiliser-buying-guide) sets the decision order. The [Wolf-Garten lawn fertiliser comparison](/hub/fertiliser-soil-and-bark-mulch/wolf-garden-lawn-fertiliser) covers another brand for the same job.
A Substral lawn fertiliser, on these amazon.co.uk listings, is a granule or a liquid sold to feed lawn grass, sometimes with an iron, moss, weed or seed claim.
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What job are you buying for?
This liquid iron feed is the strongest-rated listing in the comparison, with 4.6 out of 5 from 848 ratings, and it is intended for lawns and other plants showing an iron need. At £15.35, it also has the lowest shelf price in this seven-product set. However, the listing does not provide a square-metre coverage, an NPK analysis or a usable dilution rate, so you cannot plan a lawn treatment confidently from the details on the listing alone. The pack information is internally inconsistent: the unit count says 250 ml while the liquid-volume field says 2,000 ml. Its bullets do not make a moss-killing claim, and a high rating should not be read as evidence that it controls moss. It is a focused iron product rather than a complete seasonal lawn-feeding programme.
Pros
Cons
Best for: Lawns or other plants where an iron feed is specifically required and the bottle label can be checked before mixing.
Less suitable: A complete spring or autumn lawn programme, or anyone who needs a verified mosskiller or clear coverage figure.
Specifications
Common questions
Is this only for lawns?
The bullets say it suits various plants and is ideal for lawns and turf grasses.
What size is the bottle?
The unit count is 250 millilitres and the liquid-volume field is 2,000 millilitres. Both are on the listing.
Does the listing answer the pet question?
No. The page asks if it is safe for pets, and the specification block does not answer.
This 4.2 kg granular feed gives one of the clearer application profiles in the set: about 140 m², a stated 6:5:10 ratio and use from March to September. The listing says to apply it to a damp lawn and allows up to three uses in a season. At £49.25, the stated coverage works out at roughly £0.35 per square metre for one application. Its wording is about helping the lawn compete with moss, which is not the same as a verified moss-killing claim. Only seven ratings underpin the 4.5 score, so that star figure is much less established than the iron bottle's. It is a practical mid-sized growing-season feed when the area matches, but it should not be relabelled as an autumn product or an authorised mosskiller.
Pros
Cons
Best for: An all-grass lawn of about 140 m² that needs a measured granular feed during the stated March-to-September window.
Less suitable: October feeding, unmeasured hand spreading or anyone specifically seeking a verified mosskiller.
Specifications
Common questions
What area does the bag state?
About 140 square metres. The unit count is 4,200 grams and the item weight is 4.36 kg.
When does the listing say to apply it?
From March to September, on a damp lawn, up to three times in a season.
Does the listing state a spreader?
No. Spreader compatibility is not on the listing.
Express Sport & Game is the largest-area option in the comparison, with a 15 kg bag and 600 m² stated in the title. At £109.69, that is roughly £0.18 per stated square metre for one application, making it the best-value choice only when you can use most of that area in the growing season. The listing gives 14% nitrogen and 5% potassium oxide, but it does not state phosphorus. Spreaders and robotic mowers are named, which is appropriate for a bag of this size. Its 4.4 score comes from 50 ratings, while comments labelled Reviewed in Germany are mixed on the seven-day visible-result claim. No season is stated on the listing, so you should not treat it as an autumn feed or carry it into October without label support.
Pros
Cons
Best for: A very large sport or play lawn where most of the stated 600 m² coverage will be used during active growth.
Less suitable: Small lawns, autumn feeding or buyers who need a complete three-number nutrient analysis.
Specifications
Common questions
What nutrients does the listing state?
The bullets state 14% nitrogen and 5% potassium oxide. The mixing-ratio field is 14:5. Phosphorus is not stated.
What area is stated?
The title says 600 square metres. The coverage attribute says lawn and sports fields, which is not a number.
How fast does the listing say it works?
The bullets claim a visible result in 7 days and nutrient supply for up to 2 months.
Rasen-Vital is a 1-litre liquid lawn feed with an NK 3.5-3.5 line and chelated iron, mixed at 150 ml in 2.5 litres of water according to the bullets. Its liquid format can be practical when you prefer a sprayer to a granular spreader. The listing is less dependable on area: one bullet says that mix covers up to 67 m², while a separate field says 10 m². At £25.49, it remains in the lower shelf-price band, but the coverage conflict prevents a reliable cost-per-square-metre comparison. The title and use wording mention weeds and moss, yet the listing contains no HSE authorisation number. You should therefore follow the physical label and not increase the concentration to chase a faster result.
Pros
Cons
Best for: A measured liquid lawn feed where you can verify the bottle label and apply the stated mix evenly.
Less suitable: Cost-per-area comparisons or moss and weed treatment without first confirming the product's authorised label.
Specifications
Common questions
How do you dilute it?
The bullets say 150 ml of concentrate in 2.5 litres of water. The mixing-ratio field is 1:16.7.
What area does one mix cover?
The bullets say up to 67 square metres. The coverage field says 10 square metres. Both are on the listing.
Does the listing claim weed and moss control?
Yes, the title and the specific-uses line say weeds and moss. The listing does not contain an HSE authorisation number.
These organic lawn granules are positioned as a soil-conditioning feed and come with a 2,800 g unit count. The listing has 4.1 out of 5 from 222 ratings, giving it more rating history than most of the larger granular bags here. Its main weakness is planning: the coverage field says only Low, not a number of square metres, and no application rate is stated. The listing also states neither an NPK line nor a season, so the £33.25 price cannot be converted into a meaningful treatment cost. Nothing in the specification says that it controls weeds or moss, or that it is pet-safe. It suits a reader willing to verify the bag instructions, but it is not the transparent choice for comparing dose and coverage online.
Pros
Cons
Best for: Readers seeking an organic granular feed who can check the bag for dose, timing and precautions before use.
Less suitable: Anyone comparing cost per square metre or needing a stated nutrient analysis, weed treatment or pet interval.
Specifications
Common questions
How many square metres does this bag cover?
The listing does not give square metres. The coverage attribute is Low.
Does the listing say it controls weeds?
No. A shopper question asks about weed control, and the specification block does not answer it.
Does the listing say it is pet friendly?
No. A shopper question asks, and the specification block does not state a pet interval.
Premium Sport & Play is the clearest full-rate spring option here, with a 10 kg bag covering 400 m² at a stated 25 g/m². Its 20:5:8 line and March or April start, followed by May-to-August use, suit a dense all-grass lawn used for sport or play. The listing names spreaders and robotic mowers, which fits the large area better than hand application. At £91.10, one stated application is about £0.23 per square metre, although you must be able to use and store a large bag. A comment on the listing, labelled Reviewed in Germany, reports scorching after too much product was spread, reinforcing the need to weigh and calibrate rather than guess. The 4.1 rating comes from only ten ratings, and this high-nitrogen feed is not suitable for carrying into October.
Pros
Cons
Best for: A large, dense sport or play lawn of around 400 m² fed evenly during the stated growing-season window.
Less suitable: Small lawns, hand spreading, wildflower grass or autumn feeding.
Specifications
Common questions
What dose does the listing give?
25 g per square metre, for 400 square metres from the 10 kg bag.
How long does the listing say it lasts?
Up to 2 months. The coverage attribute uses that duration. The area is in the title.
Will it burn the lawn?
The bullets say there is no risk of burning with proper use. A comment on the listing, labelled Reviewed in Germany, describes scorch after spreading too heavily.
EasyFix combines grass seed, fertiliser and a soil improver for repair work rather than routine feeding alone. The listing states 50 g/m², up to 150 m² and a March-to-September window, and it names EasyGreen and EvenGreen spreaders. Those details make the intended job clearer than on several products in the set. However, the weight fields conflict sharply: the unit count is 7,500 g while the item weight is 758 g. There is also no Amazon star line on the listing, so there is no review score to balance against its £61.64 shelf price. Choose it for seeding thin areas only after checking the physical pack size; skip it if established grass merely needs feeding.
Pros
Cons
Best for: Repairing thin lawn areas between March and September where seed, feed and soil improver are all wanted.
Less suitable: Routine feeding of an established lawn or purchase decisions that depend on a verified online pack weight.
Specifications
Common questions
Is this only fertiliser?
No. The bullets say it combines fertiliser, grass seed and a soil improver. The item type is lawn fertiliser.
What rate and area are stated?
50 g per square metre, for up to 150 square metres, from March to September.
Which pack weight is on the listing?
The unit count is 7,500 grams and the item weight is 758 g. Both are on the listing.
We compared seven amazon.co.uk listings kept on 15 October 2026, their star lines and the public UK sources named below. Editorial scores reflect how clearly each listing states the job, season, coverage, nutrients and conflicts. They are not laboratory test results. Comments labelled Reviewed in Germany are not treated as UK review opinion.
Job and season
25%A feed is optional for many lawns, and a wildflower lawn should not be fed. We match spring nitrogen timing against autumn, and we record that none of these seven titles is an autumn-only feed.
Coverage, rate and consistency
25%We keep stated square metres and gram-per-square-metre rates, and we leave conflicting pack or coverage figures side by side rather than averaging them.
Nutrient declaration
20%A useful listing states the nutrient line. Missing NPK, phosphorus or percentages stay missing, in line with Great Britain labelling expectations.
Moss and weed claims
15%Moss and weed sentences are treated as claims. No MAPP number was recorded for these ASINs, so none is described as an HSE-authorised mosskiller.
Price and rating evidence
15%Shelf price is set against stated area only where coverage is usable. Star ratings and review counts stay with the ASIN, including a missing star line.
Start with the lawn, not the bag. Decide whether to feed, then match the season, the job and a stated coverage. Keep conflicting pack and area figures visible, and treat moss or weed wording as a claim unless the label shows an authorisation.
A Substral lawn fertiliser in this set is granules or a liquid, sold on amazon.co.uk to feed lawn grass. Some listings add an iron, moss, weed or seed claim, and those extras change the purchase. Seasonal granules, an iron liquid, a spray that mentions weeds and moss, and a seed-plus-fertiliser mix are different jobs. Decide whether to feed before you compare bags.
None of these seven titles is an autumn-only feed. The Royal Horticultural Society says not to use leftover summer feed in October. An autumn feed, if you need one, is a different lower-nitrogen product.
The organic listing's coverage attribute is the word Low, and some coverage fields use a duration such as up to 2 months. Neither is a square-metre figure.
Filling the hopper on the grass, and doubling a quiet liquid, are common mistakes. Follow the labelled rate. A comment on the Premium listing, labelled Reviewed in Germany, describes scorch after too much was spread.
Decide whether the lawn should be fed, then match the season and the job. The Royal Horticultural Society says many lawns cope without fertiliser, that drought and shade often explain weeds and moss, and that a wildflower lawn should not be fed. A spring or summer feed is higher in nitrogen and, if used, goes on in mid-spring, usually late March to April, and not after August. An autumn feed is a separate, lower-nitrogen product. None of these seven titles is an autumn-only feed.
Match area to a stated coverage and rate, and keep conflicting figures side by side. Premium is 400 square metres at 25 g per square metre. Express states 600 square metres in the title. Moos states about 140 square metres. EasyFix states 150 square metres at 50 g per square metre. The organic coverage attribute is the word Low. The iron listing gives no square metres. A Rasen-Vital bullet says up to 67 square metres from 150 ml, and the coverage field says 10 square metres.
Three typical situations, each with a recommendation from this comparison.
You want a liquid iron feed for a lawn or other plants, and you can check the bottle before mixing. Substral 7391 Iron Fertiliser Green has 4.6 from 848 ratings and the lowest shelf price here. It states no coverage, no NPK and no dilution rate.
You mow a large all-grass lawn and can use most of a stated 600 square metres during active growth. Express is the best-value option on price per stated square metre in that case. It is not an autumn feed, and phosphorus is not stated.
You are repairing thin areas between March and September and want seed, fertiliser and a soil improver together. EasyFix states 50 g per square metre and up to 150 square metres. The weight fields conflict, and there is no star line.
A stated season, a square-metre coverage and a nutrient line matter more than a moss sentence or a low shelf price on its own. Substral 7391 Iron Fertiliser Green is the top pick because it combines 4.6 from 848 ratings with the lowest shelf price, about £15.35, as a liquid iron feed. It still lacks coverage, NPK and a dilution rate, and the pack fields disagree. Substral Express Sport & Game Lawn Fertiliser is the best-value option only when you can use most of the stated 600 square metres during active growth. At about £109.69 that is roughly £0.18 per stated square metre. It is not an autumn feed, and phosphorus is not stated.
Substral 7391 Iron Fertiliser Green
It has 4.6 from 848 ratings and the lowest shelf price in the set, about £15.35, as a liquid iron feed for lawns and other plants.
Substral Express Sport & Game Lawn Fertiliser
At about £109.69 it is roughly £0.18 per stated square metre, the lowest in this set, only if you can use most of the 600 square metres during active growth.
Editorial
Products Compared publishes British-English buying guides based on amazon.co.uk listings and public UK sources. We do not run a lab and we do not invent test scores.
Guides on what to look for, how to use a product, and common mistakes.
Public UK sources and amazon.co.uk listings used for this comparison; last accessed 15 October 2026.
Expert source (DIY & tools): Lee Burkhill (Garden Ninja) (external profile) – public expert commentary used as a research source, not as a contributor to our pages.
This article contains affiliate links. If you buy a product through one of these links, we may earn a small commission at no extra cost to you. Our editorial assessment remains independent and is based on amazon.co.uk listing data and public UK sources; we did not conduct a laboratory test.
