Without water your lawn will not improve. A lawn sprinkler is the most effective way of watering turf, they attach to a hose pipe, are relatively inexpensive and simple to use.
Turf should be watered until it is thoroughly wetted to a depth of 15cm (6’’), without a soil sampling tool in can be quite hard to check this, a general guide is to apply 6cm of water over the entire lawn area (2 – 3 cm if our Wetting Agent Treatment has been applied), to find out how frequently the sprinkler needs to be moved, place a small straight sided container on part of the lawn that is covered by the sprinkler and time how long it takes for the container to fill up to 6cm. If the lawn is very dry and particularly if it is a clay based soil for the first few irrigation’s allow for 10cm to 12cm of water (4cm- 6cm if our Wetting Agent Treatment has been applied). For a drought stressed lawn to recover as quickly as possible it should be watered every three to four days (5 – 6 days if our Wetting Agent Treatment has been applied), in early morning or later on in the afternoon or evening is best, as far less will be lost to evaporation. Once the turf has recovered, this will take between a few days and a few weeks depending on the level of drought stress, decrease the frequency of watering to once per week.
Consider installing a water butt that can be used to supply your lawn with some extra water.
Bath water can be recycled and used to water your lawn, any shampoo etc in the water will not harm the lawn what so ever.
Never water little and often, as it will only hydrate the top couple of millimeters of soil above the roots and this water will evaporate the following day before being used, thus giving no benefit to the turf. It will create weak, disease prone, shallow rooting turf. It can do more harm than good giving the turf a very light watering. The lightest watering should be a minimum of 10 litres per square metre, this equates to 1cm of water. To conserve water, rather than attempting to water the whole lawn, concentrate on the most drought stressed areas.