January and February: winter dormancy
UK lawns are mostly dormant in January and February. Avoid walking on frozen or waterlogged grass, as this compacts the soil and damages the turf. If mild weather produces some growth, a light top on the highest mower setting is acceptable but rarely necessary. This is the ideal time to service your mower: sharpen blades, clean the deck, and check the spark plug or battery. Plan ahead by ordering grass seed and lawn feed for spring. In Cambridge, average soil temperature in January is around 3 to 4 degrees Celsius, well below the 6 degrees needed for active grass growth.
March and April: spring awakening
March is when most UK lawns wake up. Begin mowing when the grass starts growing, setting the mower to its highest position for the first two or three cuts. By mid-April, you can lower to your regular summer height. Apply a spring lawn fertiliser high in nitrogen (such as an NPK ratio of 12-4-6) to kick-start growth. If moss is a problem, apply a moss killer containing ferrous sulphate in late March and scarify two weeks later once the moss has blackened. ELawnCare data shows that 64% of new customer enquiries in Cambridge arrive between March and June, so book early if you want a regular gardener.
May and June: peak growth
This is the busiest period for lawn care. Mow weekly, keeping the blade at 25 to 30 millimetres for a utility lawn. Edge along paths and borders to keep the lawn looking sharp. If the lawn has bare patches after spring scarification, overseed now while conditions are warm and moist. Apply a slow-release summer feed in late May. This is also the ideal time for weed control: spot-treat broadleaf weeds like dandelions and daisies with a selective herbicide, or dig them out by hand. Water newly seeded areas during dry spells. Established lawns in Cambridge rarely need watering before July, as average rainfall is sufficient.
July and August: summer maintenance
Raise the mowing height to 30 to 40 millimetres during hot or dry weather. Longer grass retains soil moisture and stays greener. If a drought ban is in force, let the lawn go brown naturally. It will recover when rain returns. Grass that goes brown in a UK summer is dormant, not dead. Continue mowing but less frequently, perhaps every 10 days instead of weekly. Avoid applying fertiliser during drought as it can scorch the grass. If you water the lawn, do it early in the morning and soak deeply (25 millimetres of water per session) rather than little and often, which encourages shallow rooting.
September and October: autumn recovery
Autumn is the most important season for lawn improvement. Scarify in early September to remove thatch and moss. Aerate compacted areas with a hollow-tine aerator. Overseed any bare or thin patches with a suitable grass seed mix. Apply an autumn lawn feed high in potassium and phosphorus (such as NPK 3-12-12) to strengthen roots for winter. Reduce mowing frequency to fortnightly and gradually raise the cutting height. This is also the time to address drainage issues by top-dressing with sharp sand on heavy clay soils. In Cambridge, the soil temperature in September averages 14 to 16 degrees, perfect for seed germination and root development.
November and December: wind down
Give the lawn a final cut on a dry day in November, setting the mower to 35 to 40 millimetres. Clear fallen leaves regularly, as a thick layer smothers the grass and encourages fungal diseases like red thread and fusarium patch. Avoid walking on the lawn when it is frosted or waterlogged. If you notice orange or brown patches, these may be signs of autumn lawn disease. Reduce foot traffic on the lawn to a minimum. This is a good time to plan any landscaping changes for next spring, get your mower serviced, and clear leaves from borders and paths.