​I´Ú moss is a problem (usually only in damp, poorly drained lawns) and you want to get rid of it, try removing with a spring-tined rake first. See our guide to moss in lawns.
Algae can appear on lawns with poor drainage or excessive shade, or under the drip-line of trees. Prune back any overhanging trees or shrubs to improve airflow and light. Or consider replacing the lawn with shade-tolerant groundcover plants instead.
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Advice on jobs for december: lawns by month
Things to do in the garden this month
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