Lawns require water in order that the grass plants grow properly - and preferably lush green. For most of the year; for most lawns; there is a plentiful supply of the water required by natural means. There are also times with most lawns, when artificial methods of watering the lawn have to be considered, because of our fixation with the lush green striped lawn which is generally the centerpiece of the garden. As well as normal watering, there are several lawn cultivation operations that might require the addition of extra water.
In addition to this, newly laid lawns whether seeded or sodded - turfed - will require our intervention with water, depending upon when the new lawn was laid.
Other than climatic conditions, soil types various will determine how and when a lawn should be watered.
All of the following information is based upon your wanting the lushest of green grasses throughout most of the year - including the summer months. I have seen many fine lawns in the UK that are never watered, and yes for some of the summer, they turn brown. After that few weeks they resort to a lush green that is sometimes stronger and more lush that any lawn that has been molly-coddled with water - True!
The lawn in the image in early summer (July) - newly laid in the October of the year previous, did not receive any additional watering - other than the first watering after the turf was laid to bed the turf to the soil. It is still as green as the day it was laid - greener in fact - even after a dry spring which was once the norm in the south UK! I know this to be fact, for I personally laid and cared for the lawn for its first year of life!
Note that the grass is not mown crew-cut short, but is quite happy with its unconventional length of 3cms, and simply 'topped' each 7-10 days, depending upon my availability!
It is a photo that will be referred to throughout this article, for it has some interesting characteristics - other than being green in Summer. Of course it turned a little brown during the severest of summer month droughts, but soon reverted to green after even just a light fall of rain.
There is no science about when a lawn should be watered. It is normally quite obvious - but often exaggerated. (My lawn mailbox grows as the grass stops growing!) Much depends upon a wide range of individual characteristics, such those factors outlined in the list further down.
Almost all the information given by anyone about watering lawns can be ignored as far as newly laid lawns are concerned. Whether the new lawn area has been laid using grass seed or turf it will require intensive care during the first few months. That is NOT TO SAY 'intensive' watering!
For grass seed to germinate properly, it will require moisture in the soil. Without soil water, the grass seed will not germinate - you will have at best a patchy new lawn! The best way to ensure that grass seed germinates, is to thoroughly water your new area before you apply the grass seed. This is best carried out over a few days and ceased at least a day before you actually spread the grass seed. Your lawn seed bed should be firm enough for you to be able to walk over without leaving sunken footprints.
After the seed has been sown - depending upon soil moisture - and of course your local climate - regular watering of the seed is essential to ensure its continued growth into young grass plants which will eventually form your lawn.
A light sprinkler is best used rather than a heavy drop type - and certainly NOT a hose pipe. The young seedlings will need to establish into the soil without the soil being washed away from their ne root system. Do NOT water, just for the sake of watering as is often the case. Too much watering and little drying out can cause disease to the young lawn seedlings. You should be able to see if there is soil moisture simply by scraping the top centimeter of soil away - or even digging your finger into the fine tilth which you should have prepared prior to seeding.
As the grass grows and starts to need mowing, then watering can be eased off and a normal watering regime adopted. How much and when will be determined by reference to the list below.
For Newly laid Turf - sod lawns, there will not be such a need for too much soil moisture before laying the turf, for the turf will require watering after laying to help it bed into the soil below. Any type of sprinkler is suited to turf for there is little chance of damaging the protected root system.
The need for additional watering can easily be assessed by gently lifting the corner of one of the turfs to see if there is adequate soil moisture below. Once the toots start to penetrate into the soil, than a visual approach is necessary. Newly laid turf lawns will normally require watering daily in hot spring, summer or autumn months - if there is no substantial rain. The watering should be heavy enough to be able to penetrate down into the root and soil area - not simply dampen the top grass.
Drying out between watering is essential, so as not to flood the root system. If patches of turf turn brown it will almost certainly be because of lack of water - especially where abutting fences, walls and under trees and shrubs.
You should continue watering for several weeks - maybe a month or so - and intermittently through the first six months of new turf life. If the turf was laid in the Autumn, then it should be able to take care of itself until the following spring.
Whatever the season, be aware that winds dry out grass and soil surface considerably. Continual wind in the spring is particularly adept at drying out soil moisture.
Watering Established Lawns - is one of the most difficult to assess and write about in general terms. Every lawn will be different, and will require different watering regimes. This can be so with neighboring lawns as well as being different in geographical areas!
The established lawn in the image above is never watered, receives public foot traffic, is on easy to dry-out silt soil, never gets any preferential treatment. It gets mown only when necessary - and never short. The owner accepts that it will turn brown on many occasions in the summer - maybe he does not like that, but accepts it! Once it rains, then it is soon back to a normal healthy green, and because it grows to well, there is no significant weed growth. The weeds cannot compete with the strong-growing grasses!
If that does not suit you, and you insist on having a lush velvet lawn throughout the summer, then water as and when necessary to attain that utopia. Every lawn is different with differing watering requirements.
Ideally, your lawn should be watered well just before it starts to turn dry and brown! Experience only, will determine when this is so. Otherwise you can have your sprinklers on auto to water if needed or not - at a given time that is convenient to you.
In short, an established lawn may need watering daily, weekly, or even monthly dependent upon a host of different circumstances. When you do water, ensure that there is enough going on to penetrate down into the root system at least. Far better a good soaking every week with drying out in between waterings, than a light drizzle every day!
Some grasses such as Fescues are widely used in UK lawn mixes, and are generally quite tolerant of drought conditions. As with Kentucky Blue Grass used in the USA, they grow better on lighter sandy soils. You would expect grass types that grow on sandy soils to have a considerable tolerance to drying out. Many fine ornamental lawns in the UK have Browntop/Bents in the mixture, and these are not best equipped to deal with drought - and will require substantial watering - Bowling greens etc. However, Browntop grass seed will perform well if only consisting of around 10% of the total mixture.
Heavy silt or clay soils - or even good balanced loam will require less watering than light sandy soils. The soil type will also determine which grasses will be in your lawn over time. Fine grasses such as agrostis and some fescue do better in light soil, and will eventually die out over time in a heavy soil. Soil acidity also determines which grasses will grow!
Generally, the less you mow your low, the less watering it will require. This may go against the natural reaction that more foliage demands more water! It is all about growth. If you cut short and often, the grass plants will need to put on the growth with the foliage, in order to provide the roots and the rest of the plant with the nutrients it needs - hence more rapid growth = more water required. Cut the grass less in the hot summer, and growth will slow down. It is all about balance. More cutting - mor watering. Less cutting - less watering. Try it!
If you accept that browned lawns will return to normal after a rain shower, then watering becomes less important. If you just must have a show lawn, then yes, you will need to water in hot dry summers.
Surface compaction of the top layer of soil - up to 3in (75mm) deep, can prevent much of the water from soaking down on some soils - especially if your lawn is on a slope.
How you care for your lawn will have quite a bearing on how often you will need to water it in the dry summer. A well maintained lawn, regularly de-thatched, aerated and spiked, together with annual top dressing, will need less watering when the going gets tough.
The areas under trees are best left uncut in the dry weather - or at many other times of the year. Next to shrub or perennial borders may also start to brown up as the roots from the borders compete for available moisture. A drip line along the line of the lawn edging - laid down in the dip - will be a great help in areas where there is minimal summer rainfall.
Like so many things in gardening, there is no 'one answer suits all' to the question of how and when to water a lawn! Nothing will beat experience. Hopefully the info above will help.
Sandy soils are those which have a larger proportion of sand particles than they do silt or clay particles. There is is ‘universal’ sandy soil, for they can vary considerably according to the type of sand, geo-location and factors such as organic content. It is possible therefore to have a very light sandy soil or one that verges on the classification of silt soil. Optimally, a soil which is classed as a sandy loam would be ideal. However, we rarely get to choose!
Clay soils are possibly the most difficult to improve, but do have a real advantage over sandy soils - so don't start feeling sorry for yourself just yet.
They are sticky when wet, and form hard lumps, which are impossible to break down when dry. In hot weather they form large, deep, cracks. These cracks can rupture roots, and cause moisture loss - which makes the problem even worse. Regular hoeing helps to fill the cracks and forms a surface mulch, which will help retain the soil moisture.
The term ‘loam soil’ often bemuses gardeners and is rarely described, but often used with planting instructions for certain plants. Most garden plants it seems prefer to be planted in loam or fertile soil.
There are several definitions as to what constitutes a loam soil, but most agree that loam soils are generally made up of near equal parts of clay, sand and silt particles – generally a smaller ratio of clay particles. Those are the important ingredients that define a loamy soil.