Viano MO Bacter Organic Lawn Fertiliser & Moss Killer - 20kg

Firstly, This Stuff Works! I am not an expert gardener, I have a small lawn in my back garden that I have tended for decades. It is partly shaded by a wall to the south which means moss! This stuff was the bane of my life, I have treated the lawn with many brands of "weed, feed and mosskiller", they all killed the moss turning it black, and then brown when it dried out. The dead moss stayed preventing grass growth and had to be raked out. The moss always returned very quickly. I could no longer use the chemicals as I put a small tree into the lawn centre, so I tried MO Bacter. The MO Bacter killed the moss in about a week, then the moss simply vanished, no raking needed. Not only that, but grass began to grow in the space vacated by the moss very quickly. I am over two months on and my lawn is still completely moss-free, this is the longest time I can ever remember it in this state. They claim three months per application, and it is certainly looking as though this will be true as there is still no sign of moss regrowth despite some very wet weather. On the Cons side:- a) It does not "green" a lawn as strongly as Weed, Feed, and Mosskiller, used to, but if you wanted this you could always add straight lawn fertiliser. b) It does not kill weeds, but regular mowing and spot weeder keeps these down well. c) When first applied there is a strong smell of pig poo, which I suspect is a key ingredient. This goes after about week. d) It seemed a bit pricey compared to other treatments, but when I saw the results, my mind changed quickly to "it's worth every penny". If you have moss in a lawn, do yourself a favour and get this stuff, it is absolute magic.

Bought this 20kg bag of Viano MO Bacter Organic Lawn Fertiliser & Moss Killer because my British lawn was looking more like a mossy carpet than anything green and proud. For £42 I was expecting miracles, or at least a polite whisper of effectiveness. The smell though… dear lord. This stuff absolutely honks. Proper nuclear-level stink that hits you like a wet welly full of old silage and regret. I could smell it from the shed, the neighbours probably thought I’d buried something dodgy in the garden. Even after spreading it, the entire back garden smelled like a farmyard that had given up on life. I had to apologise to the missus and the dog for a solid week. On the plus side, it does eventually murder the moss. After a couple of weeks and some proper British drizzle, the moss started turning brown and giving up the ghost. The grass perked up too, so credit where it’s due. Solid organic product that works, just be prepared for the stench of a thousand disappointed cows. If you’ve got a big moss problem and a strong stomach (and deep pockets), it’s decent. But £42 for a bag that clears your sinuses and empties the garden of all living things (including visitors) is steep. 4/5 — great results, traumatising aroma. Would buy again… but only if the neighbours are away.

We’ve had moss for 25 years. We had green thumb for 20. They never got on top of it. We canned green thumb and bought this. Eradicated in one go. It’s expensive, it doesn’t go far, but it works. And the lawn goes an immense dark green for about 8 weeks. Use it every spring now, with a cheaper weed feed and moss killer in autumn. Moss hasn’t returned yet.

I first purchased the Viano MO Bacter organic lawn fertiliser early in 2026 after reading a number of reviews. I did think it wasn't cheap (I'm not a 'proper' dedicated gardener lets say), but, when you compare the price to other products that don't work as effectively and more often than not, need you to rake out / scarify the lawn, I thought I'd give it a go. I'm glad I did. If you manually rake out your lawn, as I do, it takes some time and effort and I have over many years always been disappointed with the outcomes of whatever products I used. This time, the results are very different. I tried to make sure to follow the directions as closely as possible for how much to use for the area I was covering. It seems strange to say, but the size of the granules, for me, made it easier to distribute correctly. Yes, it does smell, but, it is organic, so that's to be expected. I just love the fact that you apply the product to your lawn (it needs to be lightly watered if it doesn't rain within 7 days), the lawn in areas will discolour slightly as it starts to work and then the moss drops down into the soil/grass to be used as a natural organic food for the lawn, genius! The smell does last for a few days once used, but again, when you factor in, it is made to be organic, so it is non-toxic to children and domestic and wild animals, that's a small price to pay. The final pay off comes a little later as from my encounter with this product, my grass was greener and it had definitely got rid of the vast majority of the moss. The very little bit that remained was tiny and hardly noticeable, this was a vast improvement on any other product I've ever used. The 20kg bag gave me a first treatment in spring (using half the bag) and then a 2nd treatment (with the other half) in September. I don't like wasting money, so the final thing to say is.......I've just purchased my second bag of this product which I will use again next year, again applying in spring and then again in September, a great product I would thoroughly recommend.

brilliant product reduced the moss on my lawn to next to nothing , great for shaded areas ,Brucie bonus feeds the lawn as well

If like me you are buying this primary for killing or controlling moss, it’s not the best I have used. I have used it three times on a very large are and it’s not cheap, I would say for the summer months the lawn looks better and the moss is less evident and the grass looks healthier, but it’s not killing weeds and the moss will gradually start to come back. I used it this autumn hoping to keep the moss at bay over the winter and this time it have very little effect, for nearly 500 quid I am feeling a little peeved. ( this is dosing to around 150 grams per square meter ) I really like the idea of it being safe for pets and not having to rake but I am going to be looking for other options come spring growing season. Photo on the left are after the first treatment last on is the second treatment, starting to look better but the moss is still there, I think you would have to be treating ever 100 days.

I bought this product from Longacres quite some time ,and I can vouch for it,s effectiveness ,did the job properly,no disruptive effects, a raucous Jack Russel found it ideal for misbehaving,but seriously a damn good product ,but crikey guys that,s a helluva price, too expensive for me to re-order

Honestly, this stuff is like your normal garden centre 'weed & feed' type product IF it came back from thre future, and was given lawn steroids, and was blessed by all the theoretical deities to resolve lawn issues. I've been battling a horrific onslaught of moss for about 20 years now in my garden and all the normal Quick Fix type boxes of lawn help have definitely made the grass more green when I've used them, but aside from a few that actually did kill moss (and left unsightly dark patches on lawn) and still needed scarifying, this stuff actually works more mid-long term! You won't notice the grass miraculously turning 'lush' in 7 days like those other products, but give a bit of patience and in a few weeks or so, it starts to improve a lot. My lawn has never looked so consistent in colour and, erm,.... grassness. Seriously, not going back to anything else after this. It's possible it should be outlawed as Lawn Witchcraft. I used half a 20kg bag in spring and the other half in autumn, and now we're just starting spring again (the next one, I haven't gone back in time) and my lawn is approximately 293% better looking than it normally is at this time of year. Lush green from the winter get go, WAY less moss overall, and just a garden that looks keen for spring to roll on compared to previous years where I look out and sigh about all the moss hassle I'm going to have to endure. Superb.