Gardencare manufacturer claims testers did not follow pack instructions, as Which? Gardening issues a 'Don't Buy' warning on Miracle-Gro Moisture Control Compost.
The Scotts Miracle-Gro Company has hit back after one of its leading products was branded a 'Don't Buy' compost in Which? Gardening's latest report on container compost.

The manufacturer is adamant that the product was not used according to the instructions provided and that additional nutrients added at the time of potting affected the compost's performance.

The trial, which was published in the March issue, saw experts plant 936 impatiens and 312 seed potatoes in 624 containers last spring to test the 26 different brands of compost on test.

Testers then assessed the impatiens for flowering between June and October, while the potatoes were harvested in August and their yield and quality recorded.

Miracle-Gro Moisture Control Compost scored just 31% and was dubbed a 'Don't Buy' compost. Which? Gardening said of the product: "This compost received the lowest score. The impatiens preformed poorly from the start - they showed signs of nutrient deficiency within the first few weeks and were less vigorous than impatiens in the other composts on test. We harvested 0.5kg fewer potatoes on average from this compost than from our Best Buys. Compost quality also varied from bag to bag."

However, Scotts contests this result and argues that the addition of a slow-release fertiliser, which was incorporated into each pot of compost at the start of the trial, affected the nutrient balance in the soil.

A spokesperson for the company said: "Miracle-Gro Moisture Control Compost was not used in the trial according to the instructions on the label. The Which? Gardening report indicates that further nutrients were added to the compost (and all the others) at the time of potting, dangerously increasing the nutrient levels of this already rich compost."

They added: "Another indicator that the care regime recommended may not have been followed is that Scotts' price fighting brand, Murphy Multi Purpose Compost, outperformed most other products in the trial - even Miracle-Gro Moisture Control Compost. This has not happened before in any of Scotts trials."

Scotts explained that it had carried out "hundreds" of growing trials, which showed the Moisture Control Compost to offer "superior performance to almost all other composts on the market" and that it had received letters of praise from consumers.

Scotts concluded: "The company will be speaking to Which? Gardening to clarify what went wrong and to explore the validity of testing composts by adding further nutrients at the time of potting."

Vital Earth Tub and Basket Compost and New Horizon Multi-Purpose Compost topped the bill in the Which? trial, scoring 83% and 82% respectively.