I would like to aerate my lawn but do not poses a lawn aerator. Would spiking the lawn with a garden fork be sufficient in aerating the soil or is it simply going to further compact the soil around the holes it creates?
For once I have to disagree with Bamboo! Poking tines in the ground actually compresses soil further. Proper aeration is only done by REMOVING cores of soil and allowing these cores to disintegrate on top of the lawn. Very inexpensive to go rent one of these machines and usually works out well if you talk to your neighbors and share the machine. All lawns need aeration at least once per year. Think about it...push something down in the soil and the soil surrounding justs gets tighter. Pulling plugs of soil out of the lawn albeit only 3 or 4 inches deep is all that is necessary seeing roots of lawns are only 3-4 inches in depth. Those that have trained their lawns with proper watering will have roots down 6" but not necessary to reach that far. This breaks up lawn debris and congested roots. Gives air to bacteria necessary for breaking down debris. If your lawn is used more than normal ie) volley ball, lots of kids, big parties it would behove one to do twice a year aeration!! Got this info from master gardeners over and over again but I am sure it is out there on the internet. Maybe I should go find a site and post it here, huh? Sigh and grins!
Not only is it as good as an actual lawn aerating machine, its better - but it's time consuming and there's a knack to it. You need to insert the fork vertically and remove it in the same direction without tipping it either back or forward. Once you've inserted it, stand on it to make sure the tines go down to a good four inches, then pull it out. A little wiggle from front to back if it gets stuck won't do any harm, but ensure you pull it out vertically once you've done that so you don't break and lift the turf. Space the holes you make no more than 8 inches apart, and preferably 6 inches. If you're going to brush some kind of topdressing into the holes you've made, its best if you can use good loam mixed with sand, but you don't have to topdress.
Aeration is best carried out in autumn (though it depends where you live and what type of grass), and best restricted to areas of lawn which are obviously compacted - so where foot traffic is highest, or you notice water collects and doesn't drain easily, where it may get dry and brown more quickly than the rest, or there's poor grass vigour. It is not necessary to aerate the whole area if most of it is growing well.
As for 'making the problem worse', you haven't said what the problem is, so can't comment... unless you mean does fork aeration cause more compaction. Despite what you may have read, it doesn't in my experience, it helps. Technically, carrying out aeration with a machine is much the same process as with a fork, unless you're using a plug aeration machine, which might be marginally better for very heavily compacted ground.