This was the conclusion given by Dr Rosemary Collier - research director of the new Warwick Crop Centre - on her work on a LINK project that aimed to find out whether or not companion planting was an effective method of controlling insect pests in brassica crops.
Collier told delegates at Elsoms' brassica conference last week that the project's final field trials on cauliflower showed that lettuce reduced cabbage root fly damage to cauliflower roots "most consistently" but was not as effective as insecticidal drenches of Dursban or Tracer.
However, lettuce (at two seeds per module) was more competitive than other companion plants trialled - namely carrot and bird's foot trefoil (at four seeds per module). So the cauliflower harvested with the lettuce suffered at the hands of its companion, having symptoms such as smaller curds.
Delegates also learned that another new LINK project, which has three-and-a-half years to go, was focusing on better understanding the brassica flowering process.
Elsoms head of vegetable breeding Sue Kennedy explained to growers attending the event that breeders needed to understand this process in order to produce high-quality F1 brassica vegetables with a wide range of harvest periods.
She explained that researchers were therefore recording the flowering times of hundreds of purple-sprouting broccoli plants to help map out its genes.
Ultimately, she said, breeders wanted to breed varieties that will give the industry better control over the supply, quality and waste levels of brassica vegetables.