It is only when weeds and bare patches appear on a lawn that the fact that grass does need special attention is brought home to the average gardener who may find, often too late, that drastic and expensive reconstruction is the only remedy.
The truth is that any lawn is a colony of different plants living in strenuous competition with each other for ground space, and requiring much more attention than the ordinary flowering plant. If conditions continuously favour the weeds, these soon gain supremacy; if they favour the grasses, weeds have no hope of gaining a foothold. Many factors play a part in the battle, and one must know exactly what to do at the right time to produce and keep a lawn in perfect condition.
If a really perfect lawn is desired, it may be advisable to lay down drains, especially on heavy clay soils. Defectiveis a common cause of poor turf, for grass cannot live on waterlogged soil and quickly becomes replaced by moss and weeds.
Where there is access to an outlet, a system of tile drains may be laid, otherwise recourse must be had to sump drainage. In this, holes or ‘sumps’ 4—6 ft. deep are dug in the wettest parts, and a few tile drains set I Y2 ft. deep led into these. The hole is then filled with stones and rubble covered with 2 ft. or so of good soil.
Where water seeps on to the lawn from higher ground, a catchment drain may be placed on the side below the slope. This is merely a trench 2 to 3 ft. deep with a tile drain on the bottom covered with stones and then filled to the top with soil.
Nothing determines the quality of turf so much as the quality of the few inches of top soil, and, in laying down a lawn, endless trouble can be saved by ensuring that this layer is satisfactory. Grass must never be planted out on subsoil. When any levelling is to be done, the top soil must be removed and set aside to be replaced after the operation.
The ideal soil for lawns is a medium, friable loam. Heavy soils drain badly in wet weather and bake hard in dry, so that the grass will not grow well; very light soils dry out quickly, so that the turf suffers readily from drought.
If the soil is very stiff and clayey, broadcast hydrated lime at the rate of y2—1 lb. per sq. yd. over the surface and mix it with the soil in order to break down the lumps into fine particles and produce a satisfactory tilth. Except during construction, lawns rarely need liming. Sharp sand, charcoal and well-rotted farmyard manure,mould, , or sewage sludge should be incorporated with the top 4 in. of clay soils to improve tilth. Sandy soils require liberal applications of peat, sewage sludge, compost and farmyard manure.
Where drainage is good, shallow cultivation — about half a spit — is all that is necessary to secure a fine enough seedbed. The seedbed must be allowed to lie fallow for at least three, and preferably four months or longer, in order to sink to its permanent level. During this period, hoe down weeds and cultivate the seedbed at monthly intervals or thereabouts. Roll or tread down with the feet. An irregular, uneven surface with lumps and hollows is difficult to correct when the lawn is established, so make every effort at this stage to secure a fine tilth and a level surface. Roll on dry days to secure the necessary firmness. Themay then be sown.
Lawns from. Only use the best . For the purely ornamental lawn it is doubtful if there is anything to beat a mixture of equal parts by weight of fescue and New Zealand bent sown at the rate of 1—2 oz. per sq. yd. Tennis lawns and lawns exposed to much wear and tear need coarser grasses, and it is best to consult a good seedsman about a mixture suitable for local conditions. Where a first class lawn is desired mixtures containing ryegrass should be avoided.
To ensure even distribution of seed, mark the lawn off into squares of equal size with string, and apply the requisite amount of seed, mixed with several times its bulk of dry sifted soil, to each square. Black cotton tied to twigs will keep birds away.
After, rake lightly, cover with a thin layer of sifted soil and roll. Thereafter, keep the ground well watered, for the germinating are easily killed oif in hot dry weather. For this reason, it is best to lawns in late August or early September rather than in March. A complete fertiliser, I.e. one containing nitrogen, phosphates and potash, should be raked in 10 days before .
Turfing. Prepare the ground as directed for seeding, and firm the surface by rolling before laying. Select a turf containing plenty of bent and fescue, and cut the turves to even size and thickness, taking care to keep the edges vertical. Trim these down to I ½ —2 in- thick before laying — the thinner the better, provided theare left. If possible cut and lay out on the same day. Bought turves are usually 3 ft. long by 1 ft. wide. If bad weather prevents turfing being undertaken immediately after delivery of the turves, unroll them and open out flat. They will be quite safe for a few weeks, whereas left unopened they rapidly turn yellow.
Set 3 to 4 rows only at a time, leaving spaces of about Yz in. between turves, then beat lightly with a wooden beating block or the back of a spade. On no account beat the turves too flat. Remedy the slightest defect in level at once by packing in or removing soil. Give no water during laying and stop work in heavy rain.
When laying turf on a slope, tread the soil well and peg the turves in. Lay the bottom and top rows horizontally and the others vertically. After the turf has been laid, brush a mixture of good loamy soil and sand into the spaces, then water until saturated. Roll next day. Do not use the lawn until the grass has taken .
Turf is best laid in late autumn or winter where there is no danger of drought, unless the grass can be kept well watered in spring.
Chamomile Lawns. Chamomile (nobilis) was used for lawns in Tudor times and has recently enjoyed a revival of popularity. It seems to succeed best on light, dry soils but dislikes close mowing and does not stand up too well to continuous hard wear. A fine turf must not be expected.
Chamomile retains its bright green colour in the driest weather and the foliage is aromatic. The soil should be prepared in the usual way and the seed sown in April or September, allowing about % oz- to 10 sq. yds. Plants raised from seed vary in habit, some being upright, others prostrate, and only the low-growing forms should be retained. These are transferred to their permanent position when large enough to handle and spaced 3—4 in. apart.
Growth will be relatively slow during the first season. The plants should be cut with shears or a light hand mower with the blades set high, to prevent flowering, otherwise they are inclined to straggle. As chamomile seed is somewhat expensive, it is a good plan to mix with ordinary grass seed. The chamomile will eventually ‘take over’ the lawn.
Making Lawns from ‘Tufts’ of Creeping Bent. A new method of making a lawn is to plant small ‘tufts’ of a selected form of creeping bent in spring or autumn. Usually offered as ‘Emerald Velvet’, it spreads rapidly, thebeing very near to the surface. It is drought-resistant but the grass should not be mown too closely — set the blades of the mower about 1 in. above soil level.
Rolling. Many amateurs misunderstand the proper function of rolling as an aid to better grass. Never use a heavy roller, and never roll when the green is either soft or hard arid dry. Before rolling, brush the grass to prevent worm casts and debris from being pressed into the turf. The object of rolling is to reduce minor irregularities and to produce a uniformly firm and even surface. Never attempt to roll untrue surfaces even. Heavy rolling of elevated portions compacts the surface, so that the soil cakes hard when dry, grass cannot grow, and bare or weedy patches are formed. The same result obtains if rolling is done when rain is falling or should the soil be at all wet. If the surface is uneven, open the turf, take out soil from beneath or add it as necessary, then replace the turf.
Weeds (including Moss). Always avoid introducing weeds by the use of cheap seed or poor quality turf. Never use farmyard manure on lawns either when preparing the soil or subsequently, unless it is thoroughly rotted so that any weed seeds are destroyed.
If surface drainage is poor, by reason of consolidation of the surface soil, the lawn should be spiked or forked — see Aeration below — to break up the hardened ground. Bad drainage leads to feeble growth of the grass and a weedy, mossy lawn.
Lack ofis another reason for abundant weeds. Unless the lawn is well nourished it cannot compete with the more rapid-growing weeds which are slow to establish themselves on a compact, well-nourished lawn. Lawn sands (consisting mainly of sulphate of iron and sulphate of ammonia) are now largely superseded by selective weedkillers of the type, which, used at the recommended dilutions, destroy a wide range of turf weeds but leave the grass unharmed. They are easily applied through a can with a fine rose, liquids being rather quicker acting and more convenient to apply than dusts. These weedkillers are usually based on MCPA or 2,4 – D (in recent years, 2, 4, 5 – T has also been used). They are available under various proprietary names and the manufacturer’s instructions should always be strictly adhered to.
They can be used throughout spring and summer, the best time being during good growing weather when the soil is sufficiently moist for vigorous growth. High temperatures generally hasten the action but cool, wet weather is unfavourable. Heavy rain soon after treatment may wash the weedkiller off the weeds and render it less effective. A second application is then required. Results are relatively slow, the final disappearance of the weeds usually taking up to two months. It is advisable (though not essential) to give a dressing of nitrogenous fertiliser such as sulphate of ammonia, about 10 days before applications as this stimulates vigorous weed growth and the weeds then absorb the material more readily as there is a greater leaf surface. Always apply the weedkiller over the whole area of grass, as it is important to destroyweeds in the soil as well as those which may be blown across from neighbouring gardens or deposited by birds. Lawns can usually be cut not less than 3 days before or after treatment. Depending on the active ingredient in the weedkiller sowing of grass seed and turfing must only be undertaken after a certain period of weeks but manufacturer’s literature always explains this very clearly. Watering cans which have been used to apply the diluted weedkiller must always be rinsed out thoroughly afterwards so that no trace of the material remains, otherwise when the can is employed again for ordinary , , shrubs and other plants may be damaged or even killed. For the same reason, never apply selective weedkiller in windy weather to avoid the slightest possibility of spray drift. On some lawns the blue-flowered filiformis may spread very rapidly. It is apparently resistant to selective weedkillers, but may be eradicated by spraying or watering with tar-oil winter wash. Use ½ pint in 3 gallons of water to treat 25 sq. yds. To kill docks, nettles, horsetail, bindweed, buttercups etc. in herbaceous borders, orchards, in fact, anywhere except on a lawn, use the spot treatment. Make up the solution as you would for lawn weedkilling and apply with an old paint or distemper brush to avoid drift on other plants. Several applications may be necessary, especially with veiy persistent weeds like bindweed and ground elder. Moss tends to be more troublesome on lawns which are too acid, badly drained or lacking in plant food. A hard, closely packed surface encourages this type of growth. There is, however, usually no single reason for the prevalence of moss and if the lawn is encouraged to grow rapidly resulting in dense, compact turf, moss will rarely gain a real foothold. Regular always helps. Do not rake moss while it is still living as this merely encourages it to spread — mosses can increase by means of special buds which become separated from the parent plant when a rake is used. Tar-oil winter wash (I part in 16 pints of water) or sulphate of iron (½ oz. in 1 gallon of water) will kill moss. Either treatment will slightly ‘yellow’ the grass but it soon recovers. Rake out the dead moss and the lawn with a quick-acting fertiliser. Mercurial preparations are also effective against moss.
Mowing. Cutting tends to make two shoots grow where only one grew before, and provided the lawn is kept well nourished, will soon produce a dense compact turf. Never allow lawn grasses to grow too long, otherwise the coarser grasses will smother out the finer. Regular light mowings (say, every 4 or 5 days) remove less plant food from the soil than occasional heavy mowings with the blades set low. The first few mowings in early spring should always be with the blades set very high. Mow throughout the year whenever there is any growth. Do not be afraid to cut in winter;‘out of season’ is an excellent way of securing the removal of the coarser grasses.
Always use the grass box if weeds are present, or the mower will effectively scatter their seeds over the lawn. Rake the lawn occasionally to lift straggly runners, and scythe off this growth. It is, however, wise to mow without a grass box during prolonged drought, also to mow less frequently. By so doing, the roots of the grasses will be shielded to some extent from hot sunlight.
Remember that close cutting and manuring go hand-in-hand, for the more closely the grass is kept cut, the smaller is thesystem and the greater the difficulty the plant has in obtaining plant food.
Watering. The essentials of good watering are that it should never be carried out when sun is shining and that the grass should receive a thorough drenching and not a light spraying each time. The precise time of day does not really matter despite the belief that evening watering is best. Provided the surface is not allowed to dry out (this will be unlikely if watering in bright sunshine is avoided) any period of the day will do. To test whether watering is required cut a small section of turf (preferably on high rather than low ground) with a knife. If the soil below is dry to a depth of 1 in. watering is essential. The ground should then be saturated not less than 3 in. deep. This means applying at least 2 gallons of water per sq. yd. To ensure that the water reaches the roots of the grasses, stab the surface with a sharp fork. To water sparingly is worse than not to water at all, for it encourages the formation of surface roots, with the double evil of causing sun scorch, and of limiting the area that the plants are able to exploit for food supply. The only time light sprinkling should be given is preliminary to drenching in order to prepare the soil for the water to soak in. Always spray the lawn, never hose it; one of the modern revolving sprinklers is a good investment.
Feeding of Lawns. A high weed population combined with sparse, pale-coloured grass are signs that the lawn is impoverished. To obtain dark green, closely knit turf, regular feeding is necessary. Any complete fertiliser with a high nitrogen content is beneficial. Two applications are advisable, the first during showery weather in April, the second about mid-June. Applications after the end of July are inadvisable as they encourage soft growth which may succumb to fungus diseases. Autumn feeding may follow early autumn spiking — see AERATION, below. Two or three light dressings are preferable to one heavy application — wait for the grass to grow through before applying, the next dressing. This treatment helps to maintain a level surface and improves the texture of both heavy and light soil.
Leatherjackcts: these (the larvae of the daddy-long-legs or crane fly) will sometimeson the roots of the grass, which eventually shows brown or yellow patches especially in dry weather. Birds feeding on the lawn often indicate leatherjacket activity. Gardens near the sea appear more liable to attack. The best treatment is to apply a BHC during mild, damp weather in December. The dull, earthy-coloured grubs are then very active.
Fiisariiim Patch Disease: causes most damage during mild, moist weather in September and October, and sometimes later. Symptoms are small yellow or brown patches about the size of a penny. They may eventually be I ft. in diameter. A white or pink cotton-like growth often appears on the patches. Infected grass usually dies. Sulphate of iron will arrest the trouble ( ½ oz. in I gallon of water to cover approximately 2 sq. yds.). Thiram and mercurial fungicide are also effective. Fairy rings: characterised by rings of dark green grass encircling a weakly or bare zone. The rings are often surrounded by the reddish-buff fruiting bodies of the fungus. Digging out and replacing with new, clean soil is a popular remedy but it is often difficult to remove every portion of infected soil. Various chemical treatments have been partially successful. The best is possibly formaldehyde but before using this gardeners should obtain expert advice from an insecticide manufacturer as the perfect technique for application has yet to be discovered.
Aeration. It often happens that the surface quarter of an inch or so of soil becomes very hard owing to heavy rolling, cutting, or trampling when the soil is moist. Rainwater then takes a long time to drain away, the soil becomes sodden, and moss and bare patches soon appear. The remedy consists in piercing, or ‘spiking’, to break the surface layer and aerate the soil, preferably in autumn when the lawn is being laid up for winter.
Spiking is done by means of a fork having straight prongs about 4 in. long, 2 in. apart, and ½ in. thick in cross section, and a cross bar long enough to lean upon as a handle. At about 4 in. intervals, the fork is pressed to its full depth into the ground, and then removed, leaving distinct perforations. Another method is to use a hollow-tined fork which removes small cores of sod, or the sod may be gently eased up by means of an ordinary grape fork until the surface cracks, taking care not to disturb the level too much. Spiking is particularly valuable when carried out in early autumn before frosts begin.
After spiking, a mixture of well-rotted compost, peat and coarse sharp sand should be spread over the surface, using the back of a rake or other suitable implement, so that the material fills the holes and provides permanent channels for drainage and aeration.
Regular raking is also beneficial, helping rain, light and air to penetrate properly. Grass is encouraged to grow more upright and the runners of clover and other low-growing weeds are thereby raised from the ground, facilitating cutting by the mower.
To open up the surface soil and prevent dampness on heavy clay soils, give a good dressing every autumn of a coarse-grained sand. Some of the sands commonly used are far too fine.
Worms. Although worms are first class soil aerators in the garden generally they are a nuisance on lawns and must be exterminated where plentiful as their casts form miniature seedbeds for weeds. This is one reason why greens cleared of worms are freer from weeds. Unless worm casts are swept aside before rolling, they become pressed into the soil to form hard plugs through which grass cannot grow. Worms are usually more abundant on rich soils or heavy, wet land. Worms are easily eradicated by applying Mowrah meal, tea seed cake or derris preparations. Scatter the powder over the surface and water it well in. Be lavish with the water and thoroughly drench the soil. In a short time the worms will come to the surface, when they must be brushed up and removed, or left to be picked up by birds. Worming should preferably be done during the breeding season in spring or autumn when the weather is mild and wet and the worms are close to the surface.
Treatment of Bare Patches:
On a well-kept lawn bare patches should never be allowed to form, but on tennis courts and lawns subject to much trampling they cannot always be prevented. Repair work should be put in hand as soon as any wear or tear is observed. Treatment consists in first removing any moss and breaking the hard surface layer, then piercing the1 ground closely, and brushing a mixture of sand and compost into the holes. A complete fertiliser is then applied, and a few days later, seeds are sown and covered with light soil. Keep the patches well watered in dry weather, and avoid them when mowing the lawn. Use a scythe or garden shears to clip the young grass for the first time when it is 2 — 3 in. high.