Taking care of the Lawn in September
There is still plenty of time to in September sow new lawns, but don't to delay beyond September since diseases can attack the weak seedlings. Details of sowing a new lawn are provided in August Lawn Care.
New Lawn Care
Any lawns that were sown last month or earlier this month can be expected to germinate and start showing green after around 10 to 14 days, provided that the ground has been kept moist. Any stones that appear should be removed without delay. Once this is done and the new grass has grown to about 2 to 3 cm (1 in) high, it can be given a light rolling to settle the surface so that grass seedlings are bedded-in. Do not do any heavy rolling, especially when the soil is wet, as this will cause compaction. Most of the weeds appearing at this time of year will be annuals and are usually killed after a few mowings.
The first main cut should be applied when the grass is around 6·5 cm (2.5 in) long, and the mower blades should be set to at least 2·5 cm (1 in) high. This will tidy the lawn and encourage the grass to break out from the base and thicken up. The mowings should then be collected and disposed of because there will almost certainly be a lot of weed seeds amongst them. Whatever kind of mower you use, it must be really sharp so that the blades of grass are cut through or the grasses may just be torn out of the ground. Therefore a rotary mower is better than a cylinder type in this case.
Autumn Lawn Pests and Problems
During the early autumn some lawns may attract starlings, which feed on leatherjackets near the surface. Leatherjackets are the grubs of the 'daddy-long-legs' that feed on the roots of the grass. In a dry autumn, they can even kill large patches of the grass. If a large number of starlings are gathering on the lawn, it is usually wise to use a lawn pest killer or other soil insecticide as a precaution.
Worms will also resume their feeding nearer the surface now that the soil is moister. Their casts should be brushed off before mowing. Moles too will be resuming their activities after the summer and molehills may erupt all over the lawn.
The increased moisture content of the soil in the early autumn often brings on a crop of toadstools. For the most part they are completely harmless to the grass. Water on a general or a specific lawn fungicide, to suppress them if you wish, but they will normally disappear in a couple of weeks anyway. The exception to this is the fungus that causes 'fairy rings'. This is an unsightly rather than damaging disease, and can be extremely hard to eradicate.
Bulbs for September
Bulbs in flower in September include:
Amaryllis (belladonna lilly)
Canna (Indian shot)
Colchicum (autumn crocus)
Crocosmia & montbretia
Lilium auratum & speciosum
Nerine bowdenii (cape flower, Guernsey lily, Japanese spider lily)