Research matters... Plastic mulches for broccoli

Plastic mulches generally reduce energy losses from soil that significantly raise root-zone temperature. Such improvements usually lead to yield increases in field-grown crops.

The experiments reported here were conducted in Georgia, US, to record the effects of coloured mulches on root-zone temperatures, plant growth and yield of broccoli. Six-week-old transplants of cv. Packman were planted 30cm apart in rows on 7 October 2004, 25 March 2005 and 9 October 2008. Five plastic mulches and a bare-soil control were compared in the first two experiments, but in the third the bare-soil treatment was replaced by red-coloured plastic mulch.

Drip irrigation was used underneath the mulches. The root-zone temperature, 10cm below soil level, was increased more by dark-coloured mulches (black, blue, red, and grey) than by light-coloured ones (silver and white). The dark-coloured mulches also produced increases in plant growth and yield but only in the spring-sown crop and then not until the mean root-zone temperature exceeded 21 degsC with this cultivar.

However, root-zone temperatures above 25 degsC are detrimental and more likely under dark mulches in summer. The heads of autumn-sown crops suffered chilling injury if frosts occurred before harvesting.

Root Zone Temperature, Plant Growth and Yield of Broccoli (Brassica oleracea (Plenck) var. italica) as Affected by Plastic Film Mulches by Diaz-Perez (2009). Scientia Horticulturae 123 (2): 156-163. The contents of issues of Scientia Horticulturae and abstracts of papers are provided at

Have you registered with us yet?

Register now to enjoy more articles and free email bulletins

Sign up now
Already registered?
Sign in

Before commenting please read our rules for commenting on articles.

If you see a comment you find offensive, you can flag it as inappropriate. In the top right-hand corner of an individual comment, you will see 'flag as inappropriate'. Clicking this prompts us to review the comment. For further information see our rules for commenting on articles.

comments powered by Disqus

Read These Next

What does the 25-year plan mean for growers?

What does the 25-year plan mean for growers?

Published on 11 January, the Government's long-awaited 'A Green Future: Our 25 Year Plan to Improve the Environment' brings together a number of policy strands into a single framework that will impact many sectors, not least fresh produce, over the coming decades.

What will 'embracing change' mean for horticulture?

What will 'embracing change' mean for horticulture?

At the Oxford Farming Conference, whose theme was "embracing change", Defra secretary Michael Gove expanded on what a post-Brexit UK agriculture and land-use policy will look like and how it will impact farmers and growers.

Can growers see off the looming labour crisis by boosting efficiency?

Can growers see off the looming labour crisis by boosting efficiency?

Concern over the availability of seasonal labour to the fresh-produce industry has never been greater.