In dry conditions, the grass quickly turns unsightly yellow or brown. But it doesn’t have to come to that! With targeted measures, you can improve your lawn and make it more stress-tolerant. Proper watering will build up a deep and strong root system, and you can already rely on the ideal seed mixture when you plant a new lawn. Read here how to save your damaged lawn and prepare it for a hot summer.
Not a drop from the sky for weeks, the lawn turns brown, and you ask yourself the anxious question whether there is any life left in the turf. However, a heavy rainfall or a penetrating watering often makes the blades green up again. Lucky! The grasses were only in a dormant state. If the soil temperature rises above 30 degrees Celsius or there is drought stress, they temporarily stop growing.
In fact, however, a long hot, dry summer can permanently damage the plants, so you really have to take action. Because after a certain point, the root hairs of the grasses and sometimes even whole root sections die.
The following applies: The weaker the root system of the lawn, the more severe the damage caused by drought can be.
Dried out lawn: How to take precautions
Many care measures work together if the lawn is to appear a lush green for a long time. Here is an overview:
Watering: Sufficient and well-timed watering ensures strong roots and prevents drought stress. Fertilisation: A good supply of nutrients has a positive effect on resistance and root mass. Especially the supply of potassium (K) and phosphorus (P) is important for this. Cutting: Regular mowing ensures that the grasses grow well-branched and the area remains dense. Mulch mowing has become very popular as nutrients are returned and the fine overlay leads to less water loss. Sharp blades: A clean cut with well-sharpened blades allows the grasses to regenerate more quickly. This also gives pathogens hardly any chance to penetrate the plants. Soil aeration: Airy soil is very important for the development of deep roots. The lawn thatch must be combed out regularly, as it hinders the penetration of water into the soil. Aeration or aerification loosens compacted soil in depth. The application of sand also loosens heavy soils. Soil improvement: A targeted humus build-up can be brought about by using an organic fertiliser. Regular application of a thin layer of compost is an effective lawn treatment. On sandy soils, the addition of bentonite (a natural clay mineral that stores water very well) also proves effective. In stubborn cases, a soil activator also works wonders - this really gets the soil life going and the lawn thatch is broken down more quickly.
Drought-tolerant grass: the right seed does the trick
The fact that a lawn can be home to many different species is only noticeable when so-called weeds impair the uniform appearance. But there is also an enormous variety of lawn grasses, and it is worth taking a closer look at the characteristics of the individual species. Even if the lawn is not completely replanted, you should choose the right grass mixture for reseeding.
Tall fescue (Festuca arundinacea), for example, has very good heat and drought resistance. One drawback is perhaps that it is not one of the grazils among the sweet grasses – its leaves are relatively coarse. However, if it is kept to about 3 centimetres in height by mowing and is well fertilised, the result is a beautiful, dense lawn. Festuca arundinacea ‘Debussy 1’ is a recommendable, dark green variety. A good mixing partner is the meadowgrass (Poa pratensis). This is also quite drought-resistant and forms a dense sward through its long root runners.
Red fescue and sheep’s fescue are suitable for lean, light soils that do not need to be so hard-wearing. These evaporate little soil water and are thus well equipped to withstand longer dry phases.
In the meantime, many ready-made lawn mixtures for dry locations are available in the shops. Those who like to study lawn types and the individual grass species can also put together their own mix.
Mending lawns: How to repair brown or bare spots
The following measures can be carried out over a large area or in specific spots. It is best to proceed step by step.
1) Aerate the lawn
Compacted soil can also be caused by dryness. The moisture in the top layer of the lawn is then quickly depleted. This results in a poor nutrient and oxygen balance, which weakens the roots in the long term. Reseeding then also causes problems, as the seeds have difficulty gaining a foothold.
Aerating the lawn removes the felt of dead blades and moss from the turf. Manual scarifiers have rigid steel tines and are best suited for smaller areas. Aeration or aerification, on the other hand, is deeply effective. The soil is optimally supplied with oxygen and water penetrates better. So-called aerating forks are very well proven for this purpose. For larger areas there are, of course, suitable electric devices.
2) Fertilise the area
A fertiliser with a high nitrogen content can indeed work wonders: it stimulates grass growth so that smaller, bare patches are quickly filled in again. However, this also depends on which grass species is in use. For example, meadowgrass can produce new blades of grass very quickly due to its strong runners.
Slow-release fertilisers are generally recommended, as the nutrients are released slowly. In addition, reseeding protects the young seedlings, as they do not tolerate high nutrient concentrations well.
From the end of September, it is better to use an autumn lawn fertiliser. This is less nitrogenous and contains a lot of potassium. It creates the best conditions for the lawn to survive the winter.
3) Sowing seeds
If you are repairing your lawn, the following rule of thumb applies: drought-damaged areas larger than a handprint need reseeding.
It is best to wait a few days for the distributed fertiliser to take full effect (there are also special seedbed fertilisers with a high phosphorus content). And look at the weather forecast: temperatures should not drop below 10 degrees Celsius in the next 2 weeks. Because the lawn seeds need these minimum values to germinate and grow quickly. The best times to sow the seeds are spring and August and September.
Then you can start preparing the soil, because a good new start for the lawn begins with a fine seedbed. First you should remove stones and dead plant material. Then dig the soil to a depth of about 5 to 10 centimetres and pull it smooth with a rake in larger areas. Now give the area a few days before you start sowing.
The seed mixture you use determines the seed density – the manufacturer’s recommendations are usually on the packaging. Press the seed firmly or work it shallowly (to a maximum of one centimetre deep) into the soil. The seeds must be in contact with the soil to absorb water for germination.
And afterwards: Water (twice a day for about 10 to 15 minutes - for about 4 weeks) and mow (only when the new blades of grass have reached a height of 7 to 10 centimetres)... and then enjoy the summer!