Lawn Special Part 2
Im Teil 2 unseres Rasen-Specials, das wir alphabetisch aufgebaut haben, liest Du Wissenswertes über verschieden Rasenarten, übers Unkraut entfernen oder Vertikutieren. Hier im Gartenmagazin findest Du auch den ersten Teil des Rasen-Specials, in dem unser Gartenexperte Engelbert Kötter die Themen von A wie Aerifizieren bis M wie Moos im Rasen behandelt hat.
Lawn types
You are right - there really are different types of lawn. But as gardeners, we use terms in different ways: We talk about "grass types" to refer to different kinds of grass in a seed mix (normal seed mixes), e.g. festuca or lolium varieties. And we talk about "lawn types" to refer to decorative, utility, sports or other landscape lawns - because they have different functions. For example, a decorative lawn is not as resistant to stress in a domestic garden as a utility lawn, which is better suited to children's games (often referred to as a "games lawn"). However, this type of lawn would not be suitable for a football stadium because the grass is under much higher stress there. Football fields require proper sports lawns. The seed mix defines the lawn type in greater detail. After all, there is the right seed mix for each type of lawn.
Fertilising lawns
When you cut the grass, you also remove nutrients from the lawn: For each kilo of trimmings you remove around 30 grammes of nitrogen, 20 grammes of potassium and 10 grammes of phosphorous. You have to replace these nutrients. Decorative lawns need somewhat less fertiliser than lawns which are walked on or are under stress. You normally fertilise lawns every four to five weeks from March/April, ending with a final autumn fertilisation to prepare for the winter at the start/middle of September. However, differences do exist now that long-term lawn fertilisers and special autumn fertilisers have come to the market. As we keep reiterating, you must pay close attention to the manufacturer's information on lawn fertiliser packets. This can also help to answer the question of whether you can use composite fertiliser rather than lawn fertiliser. Take a look at the mix ratio of composite fertiliser - nitrogen: phosphorous: potassium. For lawns this is ideally 10:3:3-5.
Grass paving
Grass paving can be used, for example, for a car port or an access road instead of paving stones. But remember, it does not create a comfortable walking surface for people wearing high heeled shoes etc. It may even make it difficult for people wearing high heeled shoes to get in and out of the car. And another thing: When you lay the paving, make sure that the paving blocks are sufficiently filled with soil so that there is about two centimetres of space up to the top of the blocks after the soil has been compacted, to allow the stalks to grow. Paving blocks filled right to the top are comfortable to walk on but the turf gets worn down by shoes, car tyres and even mowers so that the area which you wanted to be green actually turns earth brown over time.
Renovating lawns
If there are gaps in your lawn after the winter, it is usually because people walked over it when it was covered by frost, ice and snow. Even someone running quickly over a lawn can result in brown patches where their feet touched the ground. You can usually remove small children's footprints by scarifying. The gaps are filled in quickly by new growth and if necessary you can simply plant a few more grass seeds there. You can cut out larger brown areas using a flat spade, loosen the ground and transplant some turf. It is not usually worth buying rolled turf for this. Simply take a few square centimetres of grass from the edge where nobody will notice. Larger grass renovation jobs - or even complete resowing - may be necessary if you are fighting weeds (see the relevant section).
Rolled turf
I am increasingly impressed by rolled turf - although it is expensive, it really has its benefits. In the case of smaller home lawns in particular - but also sports lawns, it solves your problems with just a few minutes of work. You simply have to level the surface, rough it up and roll out the strips close to each other. You can walk on the area immediately and place it under stress after waiting for two weeks to enable the roots establish themselves. Rolled turf extends the lawn laying season: You can start earlier in spring because you do not have to wait for sowing temperatures. In addition, you can lay grass later in autumn after temperatures have dropped below sowing levels again.
Cutting height
After sowing fresh seed, cut the grass when the stalks reach around eight centimetres. Cut it to around five centimetres now; when the grass is mown for the third or fourth time and is thicker, it can be gradually cut to three centimetres. There is no benefit in letting the lawn grow really long and then cutting it right back. The stalk always needs to have a certain length to enable photosynthesis, which is why it is better to cut grass little and often rather than all at once. For each cut, the rule of thumb is to shorten the stem by around half to two-thirds to 2.5 to 3 centimetres. Only lawns in less sunny areas can be left slightly longer, until the grass has a stem length of around five centimetres.
Removing weeds
You can use various techniques here. Smaller weeds such as veronicas and white clover can be removed with a manual scarifier. Use it frequently so that the plants are disturbed often, preventing their growth until they wither. It is best to use a larger scarifier several times on larger areas. Other weeds such as dandelions and daisies can be removed with a root weeder or an old kitchen knife. If you are persistent, you can remove a lot of weeds from your garden using mechanical means. If you are particularly concerned, you can also use a herbicide to remove lawn weeds. If a lawn has weeds all over it, it means that the weeds have overcome the grass seeds because the conditions were more favourable for their growth. You have a major problem with your lawn. The soil may be compacted (indicated by the presence of common plantain), greasy and damp (daisies and dandelions), very poor (white clover), or too acidic (moss). You should then consider removing these areas completely, creating a soil structure which is more beneficial to lawns, and resowing the whole area or covering it with rolled turf. However, we advise that you consult a local landscape gardener, because it is hard to professionally assess a surface without studying it in detail. Tip: Especially in serious cases and for larger lawns, do not use just any landscape gardener. Choose one who has extensive experience in laying lawns - such as a golf course specialist - instead of someone who simply knows how to lay natural stone walls and create swimming ponds.
Scarifying
Scarifying is great because it allows you to give grass a real good clean once, twice, or three times a year. Removing lawn thatch returns air and light to the lower parts of the grass, making the stems more vigourous. Fertiliser can reach the roots again and does not feed the moss and decay bacteria in the thatch in between. And this is certainly useful for fighting weeds. Scarify for the first time now in March, again in the middle/at the end of May and a third time at the start of September. Each time you scarify, as with mowing, change the direction from which you approach the stem and work diagonally now and again - as explained in the information on the best cutting technique above. After scarifying, add lime and fertiliser and resow gaps if necessary. It is best to carry out aerification after scarifying.