in a way that it can withstand dry phases and hot days better
Our grasses consist of up to 95% water and a loss of 5% of it leads to death. In summertime, there is a high risk of water loss, especially after cutting the lawn and during photosynthesis.
The cold zone grasses, the grasses of Central and Northern Europe, have to open the stomata to absorb CO2 - essential for photosynthesis - to be absorbed from the surrounding air.
Water evaporates - unintentionally. If the plant cannot absorb new water from the soil because it is too dry, the stomata remain closed. Photosynthesis comes to a standstill and the plant lives on its sugar reserves, which it "breathes". Most grasses can survive dry periods for a few days to weeks. If rain falls or if the lawn is irrigated and the plants can absorb water, the stomata are opened again and photosynthesis is reactivated.
Care tips to increase tolerance to drought
The tip on cutting height is very important and easy to implement. In summer - from June - the cutting height of a lawn should generally be increased by 1 - 1.5 cm. This provides more surface for photosynthesis and offers plants that strive for a balance of subterranean and aboveground substances the opportunity to form further and thus deeper roots. In this way, the grass plant can supply itself with water from the soil moisture for a longer period, even when it is dry.
In addition, potassium is an important nutrient for the grasses to tolerate drought. Potassium regulates the water balance in the plant cells.
Fully automatic irrigation systems are find everywhere today. These irrigation systems tempt you to water a few minutes a day. That is precisely what is dangerous for the grass, as the soil moisten is only very shallow. This promotes shallow-rooted and mostly undesirable grasses.
Our preferred, valuable lawn grasses, root deeper, but quickly learn that no water reaches the bottom and that they should send their roots upwards to find it. However, since the soil always dries out from top to bottom, the plants become even more sensitive to drought or more dependent on irrigation.
It is therefore better to moisten the soil at least 10 cm deep. Since every millimeter (= l / m²) of precipitation moistens the soil about one centimeter deep, at least a water supply of 10 l / m² or 10 mm is required.
Whether the goal is achieved can be checked with a rain gauge (amount of rain) or alternatively with a spade to check the moistening depth in the soil.
Saving water and protecting lawns through observation and caution
Drought and heat are already maximum stress for our lawn grasses. Any further pressure can become a question of survival if the vegetation point is demolished. Therefore, it is important to avoid everything that is additionally burdening. No cutting, no crossings and certainly no tillage or other stress-inducing maintenance measures during a massive heat or dry period.