A UK summer often brings some surprising weather, and the wettest summer on record or the driest summer on record can be just around the corner at any time. With this being the case, it is difficult to know just how much you should be watering your lawn whether it is new or established.
The most obvious indication of whether you’re watering too much, or watering too little, will be the condition of your lawn. If it is dry and yellowing, then its likely you are not watering frequently enough. Flooded and bog like – you may be over watering it.
Normal Conditions (15 degrees and below, with regular rainfall)
Established Lawn (6 months +)
In summer, UK temperatures can range from 15 – 25 degrees. Anything lower than 15 degrees could be described as ‘normal conditions. Consistent temperatures above this with no rainfall will lead to drought conditions. An established lawn in summer can be watered 2/3 times a week.
If we consider that at a minimum 8-10 degrees are required for most species to germinate, then watering once a day for the first 6-8 weeks after sowing should be suffice. Aim to water deeply once a day in this time period – ½ inch for clay soils and 1 inch for sandy / loam type (normal) is sufficient.
The first 6-8 weeks of aftercare for a newly sown lawn are critical. Grass seed needs adequate heat, water, and nutrients from the soil to germinate. A lack of any of these requirements can cause in delayed germination or failed germination entirely.
Drought Conditions (15 degrees and above, with irregular / consistently no rainfall)
In drought conditions, lawns can go for weeks without the level of moisture they require. In a drought, the water table is extremely low. The water table is essentially where water goes to once it disappears off your lawns surface. In normal weather conditions, the water table retains this water keeping your lawn moist and hydrated. In drought conditions, the water your lawn does receive is unlikely to ever reach the water table. As the water table exists in your lawn and your neighbours, you can get an idea of how low it is in your area by simply observing how everyone else’s grass is looking.
Established Lawn (6 months +)
The great thing about an established lawn is its ability to bounce back, even after being consistently subjected to dry conditions. The 'Bounce Back' test will help you to get a better understanding of your lawns condition during a drought. If you step on your lawn, and the grass does not rise back into place - then your lawn has failed the 'Bounce Back' test. For an established lawn, you should aim to water infrequently and deeply when the lawn is failing the 'Bounce Back' test. You should follow the below instructions:
- Water between 10 -14 days apart
- Soak the lawn - You should see minor puddles on the surface
- Water the grass during cooler periods - evening or night time
- Avoid watering during hot periods of the day – most of the water will evaporate
- With areas of lawn which don’t get much sun – don’t soak them as much
Rain water is much more nutritious than tap water as it contains higher levels of nitrogen ultimately boosting growth. If you can’t let nature take its course consider getting a watering butt to collect rain water throughout the year and spread on the lawn with a watering can when required.
Sowing a new lawn in drought conditions is not ideal, so consider this before sowing grass seed. A new lawn is different from an established lawn in that if the seed is not watered, it will most certainly die in drought conditions as its roots are too shallow. In drought conditions you should aim to water twice a day and deeply – maintaining the ½ inch for clay soils and 1 inch for sandy / loam type (normal) guide. If your soils are particularly dry and you find that the water absorbs quickly, try to water again in the evening when the sun is down.
It may be obvious, but if floods occur in summer it is imperative that you do not water your lawn until the flooding subsides. If you are planning to sow a new lawn, make sure to consult a two-week forecast before sowing.