Lawn care 2

There are two steps to take, first of all improve conditions for the existing grass - it's not thin and sparse for no reason - and then add to it. If you don't address underlying problems, then it will revert to how it was beforehand, so you may need to aerate with a hollow-tine aerator or fork, apply a top-dressing, remove thatch, feed, remove weeds etc.

Adding grass seed while retaining existing grass is a bit hit and miss and dependent largely on what the weather is like after seeding. Rake the surface with an ordinary garden rake to loosen the soil, preferably not disturbing existing grass too much, then sow the seed on top, rake again to cover as much of it as you can and water it.

Keep off it completely until it begins to sprout, watering where necessary, when it starts to show through don't mow it as the rest of the lawn until it has thickened up. This is a good time to apply a general lawn feed which will also encourage the existing grass.

You may need to repeat this process more than once, but you should get there with patience.

Most lawns will tend to accumulate a surface mat of dead grass and moss, old clippings and ageing leaves, immediately beneath the growing leaves, this is known as 'thatch'. As this builds up, it hinders healthy grass growth and is therefore best removed. If your lawn is especially springy to walk across, it is probably due to this thatch.

This thatch is removed by a process known as scarifying (and no it doesn't mean sneaking up to the lawn and shouting BOO!). Scarifying is a process of vigorous sweeping either manually or with a mechanical device. The purpose of this is to allow water and fertilizers to reach down more effectively to the grass roots and to allow the finer bladed grasses to grow up more easily.

The traditional way to scarify is to use a besom, a broom like a witches broomstick made of birch twigs. A more efficient modern alternative is a spring tine rake. This is used in a vigorous manner sweeping across the lawn (sweep from one side and then swap over to the other, it's excellent exercise for the waist in particular).

This will give a growing pile material (usually mainly of moss) that has been dragged out from between the growing grass plants. In the process the lawn is made quite a bit tattier than it was before you started. Don't worry about this and stop when you've removed a reasonable amount of material, you could go on and remove it all, but it would take much longer and it's a process of diminishing returns.

Neatly-trimmed edges greatly enhance a lawn. The are two tasks in lawn edging, one easy and the other considerably more work. Unfortunately - yes you've guessed it - the harder work one is the one that needs to be carried out in most gardens. 

1/ Preparing the edge with an edging tool. This is a semi-circular blade on the end of a handle, the idea is that you go along the whole length of your edges and cut a straight line (use a plank as a guide) standing firmly on the tool to cut the uneven soil so that it straight. The good news is that this doesn't need doing very often. If you have a lot of edge to do, or not enough time or energy, an electrical or gas powered machine is available to do this. Don't try using a spade, they're usually not sharp enough and are gently scalloped rather than straight.

2/ Keeping the straight edge trimmed. The much easier part of the job. Once the edge is prepared (above) then keep it looking trim by using long-handled shears or one of the strimmer models now available where the head swivels through 90° for this job. These tools will not replace the edging tool above (shame).

For most of the year, in cooler Northern regions lawns do not need watering. Occasional dry spells in spring or summer, especially in areas of light soil, may require that the grass is watered to prevent it from dying back and weakening the lawn. Avoid frequent light watering, which encourages shallow rooting, but also avoid too heavy or frequent watering, which promotes moss, disease, and largely drains away anyhow.

Very small lawns can be watered using a hosepipe with an adjustable spray nozzle, whilst a sprinkler system is ideal for a medium to large area. 

Lawns that have areas of frequent high traffic can be re-inforced so they still appear to be more like a lawn than a path but are much more hard wearing.

This is done most easily by laying pre-cast paviours or house bricks in an open pattern, and allowing grass to grow in between them, to create a hidden path. Another method is to use semi-rigid artificial netting, this allows grass to grow through and can be laid to provide a firm footing, without greatly affecting the look of the lawn. In all cases reinforcement allows weight to be more evenly distributed and to some extent taken off the grass and onto the reinforcement material, so reducing lawn damage. The downside is that it seems the more effective the reinforcement, the more visible it is.

To lay a re-inforced area of the lawn, select precast paviours with open centres, those used for screen walls for instance. A strip of turf the width of the path is first removed and the blocks laid flat into a firm bed of sand (or sand and mortar) so that their surface lies just below that of the lawn. (Allowing for a little settling, the mower should skim easily over the top of the block path without any damage to blades.)

Sieved soil is then brushed onto the blocks to fill the spaces. Grass seed is then sown into the soil and will grow to cover and hide the blocks.

The success of this type of pathway depends largely on the skill with which the blocks are laid. House bricks could also be used laid in a herringbone fashion, again to be hidden by grass. The bricks can be laid with 2 inch gaps between the rows.