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Lawn feeds and weeds

How we test lawn treatments

Article 3 of 5

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How we test lawn treatments

Discover how we test lawn-care treatments to find out which are good enough to be Best Buys.


A decent lawn-care treatment will tackle the problems with your turf and leave your lawn looking lush, but a bad one will do little to improve lawn's condition. 

Lawn-care treatments fall into two categories: standalone lawn feeds; and combined lawn feed, weed and moss killers. Use the one that matches your needs, rather than taking a blanket approach, and you'll not only fix your lawn's problems but avoid using unnecessary chemicals.

Keep reading if you what to find out what criteria we used during testing.

If you already know what you're looking for, head to our Best Buy lawn feeds and lawn feed, weed and moss killers.

Each product was tested on four randomly assigned plots of 4sq m. We also included an untreated control plot in each trial area. The products were tested on three separate areas of lawn, depending on the type of product:

  • The lawn feeds were tested on an area of neglected turf, representing a typical family back lawn.
  • The feed, weed and moss killers were tested on an area of typical lawn infested by a selection of common lawn weeds, including buttercups, dandelions, daisies, clover, plantains, speedwell and self-heal, covering almost half of the surface, and about 45% moss.
  • All the treatments were applied according to the manufacturers’ instructions and repeated, as recommended, through the summer.

Our expert assessors rated every plot regularly for colour and overall appearance, the density of the grass sward and the percentage of weeds or moss. For the weed and moss killer trials, they rated any visible injury to the grass that the product caused. They also assessed how easy each product was to apply.

The score is made up of 30% for ease of use, and the remainder is divided equally between the effectiveness of the feed, weed or moss killer components as appropriate.