Spikey

Cleavers is a native annual found in fields and hedgerows. It occurs on most soils throughout the UK but prefers nutrient-rich sites. It is considered an indicator of loam. Cleavers is most frequent on soils with a pH of 5.5 to 8.0. It has been recorded up to 1,500 ft.

Cleavers is a frequent weed of winter cereals and oilseed rape where it may grow over and drag down the crop making harvesting difficult. It forms dense patches and has a more extensive root system than many weeds or crops allowing it to survive better under dry conditions.

The occurrence of morphologically distinct ecotypes has been reported but some differences are related to habitat. Hedgerow plants are thought to differ in levels of seed dormancy from cleavers growing within the crop. The effect may be to spread the period of emergence in the field to avoid a complete loss of emerged seedlings following autumn cultivations. Potential variability due to polyploidy enables cleavers to respond to environmental conditions.

The roasted seeds are said to be an excellent substitute for coffee but as cleavers also has medicinal uses as a laxative and emetic, consumption should be in moderation. Anthoquinones in the sap may cause skin irritation.