What to do in the garden and home in September

September is the month to start lawn recovery and get spring bulbs into the ground, while also making sure the house is ready for the wetter weather that autumn brings. The soil is still warm from summer but the pressure of hot, dry weather has usually eased, which makes it a good window for jobs that need root growth without heat stress.

Lawn: scarifying and overseeding

If your lawn has gone thin or mossy over summer, early to mid-September is the right time to scarify it (rake out the dead thatch that builds up at the base of the grass) and oversee any bare patches. The soil is warm enough for new seed to germinate but the worst of the summer heat is behind you, so seedlings are less likely to scorch. In the north of England and Scotland, aim for the earlier part of the month; further south you have a bit more flexibility into early October.

Aerating (spiking or coring the lawn to relieve compaction and improve drainage) is worth doing at the same time if the lawn has been heavily used over summer or sits on heavy clay. Doing this every few years helps, since a compacted lawn will drain poorly through autumn and winter regardless of anything else you do to it.

Bulbs: plant now for spring

Daffodils and other spring-flowering bulbs go in from mid-September onwards. Tulips are the exception: they are better held back until November, because planting them too early increases the risk of a fungal disease called tulip fire.

• Choose firm, unblemished bulbs and discard any that feel soft or show mould
• Plant at a depth of roughly three times the bulb's own height
• Add grit to the base of the hole on heavy clay soils to improve drainage

Borders: cutting back and clearing

Cut back perennials that have finished flowering and are looking tired, but leave seed heads on plants like echinacea and sedum if you want to feed birds and support insects over winter. Deadheading (removing spent blooms) roses and repeat-flowering perennials now can encourage a last flush before the weather turns. This is also a sensible month to lift and divide overcrowded clumps of perennials, since the soil is still workable and there is time for new roots to establish before winter.

Around the house: gutters, fascias and the shed

Clear gutters and downpipes of the first fall of leaves before they build into a blockage. A blocked gutter overflows down the wall, and water running down brickwork over months is what causes damp problems that are far more expensive to fix than an afternoon with a ladder and a pair of gloves. While you are up there, look at the fascia and soffit boards (the trim along the roof edge) for flaking paint, cracking or soft spots, since these are early signs of water getting in.

Check the shed roof felt for lifting edges or cracking before the autumn rain sets in properly, and make sure the door still closes squarely now that damp weather can cause timber to swell. For a fuller seasonal checklist, see shed and outbuildings maintenance, and for the wider run of jobs across the garden this month, see garden maintenance. If a job here does not feel urgent, it is usually fine to leave it until October without causing harm.